Well...that's one of the reasons why I tossed Amapi 3 off my machine (no hourglass, no thermometer, just a dead interface; you couldn't tell if it was locked up or just busy.) I've had a couple legitimate lock-ups with Carrara but I forgive it; I'm on an underpowered machine with a legacy OS. I'll give it two-three minutes -- it can take that long to do a "weld" operation over a nearly completed model. I've also had an abrupt quit or two (usually when naming polys), but unlike its un-mourned ancestor, it has yet to corrupt a file on me. I just start it up again, re-save the file, and am off and running.