When trying to launch the version of Galaxy Forge that came with Sins: Rebellion, it crashes immediately.

Using the Galaxy Forge 3 from the Downloads section works, but is incompatible with Rebellion. Swapping out the GalaxyScenarioDef.galaxyScenarioDef file that came with Rebellion (Version 4?) with the Galaxy Forge 3 version (from download area of this site) makes it work, but obviously I don't have access to the new bits, like Dwarf Planets, or the Fair version of planets, etc.

Swapping out the .exe and .dll doesn't seem to have any affect. Tried looking through the GalaxyScenarioDef.galaxyScenarioDef file, but without any real knowledge of it, it's difficult for me to verify manually that the contents are correct; considering I have five versions, however, and the ones I got from my friends are confirmed to work, it seems unlikely the GalaxyScenarioDef.galaxyScenarioDef is somehow bugged.

I originally thought somehow my version was corrupted, so I got my friend to send me theirs, the entire Galaxy Forge folder. It didn't work. So I asked another friend. And another. I now have five versions, and only the one from the site, Galaxy Forge 3 allows the .exe (any .exe, either the Rebellion version or the Galaxy Forge 3 version) to launch without crashing immediately. I've compared file contects, so I'm not missing any .dlls or such, as far as I know.

.NET Framework is updated to v4.0.

I'm completely out of ideas on how to troubleshoot this. Any and all help would be greatly appreciated. If there is any more information I can provide, I would be happy to.