How do I get Extensions into the Module

Hey, I have been playing X-Wing Miniatures for a while and I have used Vassal for War Machine but I am not expert.
I am trying to make some battle reports for X-Wing but I cannot figure out how to get the Extensions into the Module.

I have downloaded these files and they are all in the same folder.
Star Wars X-Wing -Tournament.vmod module 13.18 MB 10-9-2012 3.1
X-Wing Booster -Tournament.vmdx Extension 1,015 KB 10-9-2012 3.1
Y-Wing Booster -Tournament.vmdx Extension 1.24 MB 10-9-2012 3.1
Tie Fighter Booster -Tournament.vmdx Extension 984 KB 10-9-2012 3.1
Tie Advanced Booster -Tournament.vmdx Extension 1.33 MB 10-9-2012 3.1

When I load the Module the only ships I can find are the X-Wing and Tie Fighter. I cannot get the items from the Extensions.

Thanks

Check the Vassal Help menu, and look in the User Guide. There’s an explanation of how to activate extensions on p21.

You should be able to right-click the module in your Vassal Module Library and just select Add Extension.