Stalingrad '42 Module

A question about the module for GMT’s Stalingrad '42 : How are unit counters to flipped to their reverse sides? I’m using an iMac
(macOS Mojave 10.14.6). I’m new to Vassal, so any other pointers about the module would be appreciated.

I don’t know that specific module, but in general, there will be “flip” option (or something equivalent) on the right-click menu for the counter. If you don’t have a 2nd mouse button, I believe Ctrl-Click is equivalent to right-click on Macs.

Right-click on a piece to get a context menu. You’ll find various items for adjusting pieces there. (Also, you’ll find the hotkeys for doing the same operations listed on the context menu.)

Thank you both for your assistance.