Not sure how much detail you want. I was using VASL adding overlay to board.
2022-11-21 12:30:58,255 [10416-main] INFO VASSAL.launch.StartUp - Starting
2022-11-21 12:30:58,264 [10416-main] INFO VASSAL.launch.StartUp - OS Windows 10 10.0 amd64
2022-11-21 12:30:58,264 [10416-main] INFO VASSAL.launch.StartUp - Java version 18.0.1
2022-11-21 12:30:58,264 [10416-main] INFO VASSAL.launch.StartUp - Java home C:\Program Files\VASSAL-3.6.7\jre
2022-11-21 12:30:58,264 [10416-main] INFO VASSAL.launch.StartUp - VASSAL version 3.6.7
2022-11-21 12:30:58,356 [10416-AWT-EventQueue-0] INFO VASSAL.launch.ModuleManager - Manager
2022-11-21 12:31:09,340 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.AbstractLaunchAction - Loading module file C:\Users\Intel\Documents\VASSAL\vasl-6.6.5.vmod
2022-11-21 12:31:10,099 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,105 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,106 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,111 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,116 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,118 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,119 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,120 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,124 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,125 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,199 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:31:10,200 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.launch.AbstractLaunchAction - Loading module VASL
2022-11-21 12:31:10,205 [10416-SwingWorker-pool-2-thread-1] INFO VASSAL.tools.io.ProcessLauncher - launching C:\Program Files\VASSAL-3.6.7\jre\bin\java -Xms512M -Xmx512M -Duser.home=C:\Users\Intel -Duser.dir=C:\Program Files\VASSAL-3.6.7 -cp lib\Vengine.jar VASSAL.launch.Player --load – C:\Users\Intel\Documents\VASSAL\vasl-6.6.5.vmod
2022-11-21 12:31:10,767 [21892-main] INFO VASSAL.launch.StartUp - Starting
2022-11-21 12:31:10,781 [21892-main] INFO VASSAL.launch.StartUp - OS Windows 10 10.0 amd64
2022-11-21 12:31:10,781 [21892-main] INFO VASSAL.launch.StartUp - Java version 18.0.1
2022-11-21 12:31:10,781 [21892-main] INFO VASSAL.launch.StartUp - Java home C:\Program Files\VASSAL-3.6.7\jre
2022-11-21 12:31:10,781 [21892-main] INFO VASSAL.launch.StartUp - VASSAL version 3.6.7
2022-11-21 12:31:10,782 [21892-main] INFO VASSAL.launch.Launcher - Player
2022-11-21 12:31:14,660 [21892-AWT-EventQueue-0] INFO VASSAL.build.GameModule - VASL version 6.6.5
2022-11-21 12:31:14,829 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\chit-generator-2.0.vmdx
2022-11-21 12:31:14,838 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension chit-generator-2.0 v2.0 loaded
2022-11-21 12:31:14,838 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\cloaking-display.vmdx
2022-11-21 12:31:14,854 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension cloaking-display v0.0 loaded
2022-11-21 12:31:14,855 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\hideable-control-markers-1.9.vmdx
2022-11-21 12:31:14,873 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension hideable-control-markers-1.9 v1.9 loaded
2022-11-21 12:31:14,873 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\Hollow Legions.vmdx
2022-11-21 12:31:14,910 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension Hollow Legions v0.0 loaded
2022-11-21 12:31:14,910 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\Nationality Smoke v1.0.vmdx
2022-11-21 12:31:14,915 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension Nationality Smoke v1.0 v0.0 loaded
2022-11-21 12:31:14,915 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\neals-vasl-charts-v1-5.vmdx
2022-11-21 12:31:14,918 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension neals-vasl-charts-v1-5 v1.5 loaded
2022-11-21 12:31:14,918 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\oba-flowchart.vmdx
2022-11-21 12:31:14,923 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension oba-flowchart v1.1 loaded
2022-11-21 12:31:14,923 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\scenario-aid-card_2.0.vmdx
2022-11-21 12:31:14,940 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension scenario-aid-card_2.0 v2.0 loaded
2022-11-21 12:31:14,940 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\tray.vmdx
2022-11-21 12:31:14,945 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension tray v0.0 loaded
2022-11-21 12:31:14,945 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Loading extension C:\Users\Intel\Documents\VASSAL\vasl-6.6.5_ext\VASLOverlays_v2.11.vmdx
2022-11-21 12:31:15,041 [21892-AWT-EventQueue-0] INFO VASSAL.build.module.ExtensionsLoader - Extension VASLOverlays_v2.11 v2.11 loaded
2022-11-21 12:31:27,797 [21892-AWT-EventQueue-0] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:32:39,967 [21892-AWT-EventQueue-0] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:32:57,891 [21892-AWT-EventQueue-0] INFO VASSAL.launch.TilingHandler - No images to tile.
2022-11-21 12:33:22,935 [21892-AWT-EventQueue-0] ERROR VASSAL.tools.ErrorDialog -
java.lang.NullPointerException: Cannot invoke “VASL.LOS.Map.Hex.getBaseHeight()” because the return value of “VASL.LOS.Map.Map.getHex(String)” is null
at VASL.build.module.map.boardPicker.Overlay.transform(Overlay.java:519)
at VASL.build.module.map.boardPicker.Overlay.(Overlay.java:75)
at VASL.build.module.map.boardPicker.ASLBoardSlot.overlap(ASLBoardSlot.java:194)
at VASL.build.module.map.boardPicker.ASLBoardSlot.checkOverlap(ASLBoardSlot.java:154)
at VASL.build.module.map.boardPicker.ASLBoardSlot.addOverlay(ASLBoardSlot.java:78)
at VASL.build.module.map.ASLBoardPicker$Overlayer.actionPerformed(ASLBoardPicker.java:1224)
at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2313)
at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
at java.desktop/javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:279)
at java.desktop/java.awt.Component.processMouseEvent(Component.java:6616)
at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)
at java.desktop/java.awt.Component.processEvent(Component.java:6381)
at java.desktop/java.awt.Container.processEvent(Container.java:2266)
at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4991)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)
at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)
at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:97)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:117)
at java.desktop/java.awt.WaitDispatchSupport$2.run(WaitDispatchSupport.java:191)
at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:236)
at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:234)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:318)
at java.desktop/java.awt.WaitDispatchSupport.enter(WaitDispatchSupport.java:234)
at java.desktop/java.awt.Dialog.show(Dialog.java:1080)
at java.desktop/java.awt.Component.show(Component.java:1729)
at java.desktop/java.awt.Component.setVisible(Component.java:1676)
at java.desktop/java.awt.Window.setVisible(Window.java:1036)
at java.desktop/java.awt.Dialog.setVisible(Dialog.java:1016)
at VASL.build.module.map.ASLBoardPicker.actionPerformed(ASLBoardPicker.java:832)
at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2313)
at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
at java.desktop/javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:279)
at java.desktop/java.awt.Component.processMouseEvent(Component.java:6616)
at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)
at java.desktop/java.awt.Component.processEvent(Component.java:6381)
at java.desktop/java.awt.Container.processEvent(Container.java:2266)
at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4991)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)
at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)
at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:97)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:117)
at java.desktop/java.awt.WaitDispatchSupport$2.run(WaitDispatchSupport.java:191)
at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:236)
at java.desktop/java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:234)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:318)
at java.desktop/java.awt.WaitDispatchSupport.enter(WaitDispatchSupport.java:234)
at java.desktop/java.awt.Dialog.show(Dialog.java:1080)
at java.desktop/java.awt.Component.show(Component.java:1729)
at java.desktop/java.awt.Component.setVisible(Component.java:1676)
at java.desktop/java.awt.Window.setVisible(Window.java:1036)
at java.desktop/java.awt.Dialog.setVisible(Dialog.java:1016)
at org.netbeans.api.wizard.displayer.WizardDisplayerImpl.showInDialog(WizardDisplayerImpl.java:363)
at org.netbeans.api.wizard.displayer.WizardDisplayerImpl.show(WizardDisplayerImpl.java:268)
at org.netbeans.api.wizard.WizardDisplayer.showWizard(WizardDisplayer.java:107)
at org.netbeans.api.wizard.WizardDisplayer.showWizard(WizardDisplayer.java:154)
at VASSAL.build.module.WizardSupport.showGameSetupWizard(WizardSupport.java:227)
at VASSAL.build.module.GameState.setup(GameState.java:523)
at VASSAL.build.module.GameState$8.actionPerformed(GameState.java:247)
at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)
at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2313)
at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:374)
at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1029)
at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1073)
at java.desktop/java.awt.Component.processMouseEvent(Component.java:6616)
at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)
at java.desktop/java.awt.Component.processEvent(Component.java:6381)
at java.desktop/java.awt.Container.processEvent(Container.java:2266)
at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4991)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)
at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)
at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)
at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)
at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4823)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:97)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)