Alright.

An update: When I put it in in place of the other common.lvl file then, like I said, the game doesn't run. However, when I put the old one back it it works fine again.

Hmm... weird. When I replace the old common.lvl file with this one and start the game, the screen turns black like normally when it's about to start but then it crashes/nothing happens. Do you know what could be wrong?