Have you just tried resaving all models and esp. textures involved in those rooms? Or maybe it's something else, like a globally (pre-)defined BMAP or a globally (pre-)defined sound. Does the level crash if you just load it in a different project? Probably not though, even with a faulty file.
"Falls das Resultat nicht einfach nur dermassen gut aussieht, sollten Sie nochmal von vorn anfangen..." - Manual
