But are there no two tiles that have the same model/sound/bmap? If every tile has its very own model/sound/bmap, then there is no way to get faster than these 40 seconds.

your current method of using "=" to char* actually works, but this way you can only use names you have entered somewhere in your script. That might be okay though. If this special line crashes, then how is placing_filename defined and where is it changed?

EDIT: btw: are you saving or loading levels from files?