Before anyone says, we have tried just about everything under the sun. We've made sure that we've downloaded the same mods via a collection, and ensured they were in the right order mod by mod. The only way we were able to actually play the game was by deleting all stellaris files in documents and steamapps/common, doing a fresh reinstall, and downloading the mods once we verified we have the same vanilla checksum. We still do have the same vanilla checksum as well. It's intensely frustrating when trying to play with mods in this game when the game somehow changes the checksum between boots, even though none of us have done anything. The checksum even changed when I moved between hardrives. I just have no clue what could be causing it.