.Pixote. said:
When the map tries to load and it can’t find the missing proto files…the game crashes.
Actually, that's exactly why I recommend removing the references. critters.lst contains references to proto files 484 to 507 but these files actually do
not exist in the Unofficial Patch. By leaving these references in, the chance of having a crash is actually increased. Given that there's no proto files referenced after 507 anyway (00000507.pro is the last line of the file), it shouldn't wreck anything to remove references 484 to 507.
Having said that, though, I suppose another way to resolve the issue is to include those missing proto files in the Unofficial Patch. But then that would just be introducing unneeded files.