Warning to Mappers - Save in versions

[Wanderer]

Having just ran into this problem headfirst and losing a couple of days of work... save off versions of your .map files.  I had a map corrupt somehow and the only way to get rid of the problem was to destroy every original brush on the map.  

I'm trying to figure out what caused the corruption and will post more when I do, but just a head's up.

[XaverXN]

How did this corruption show, wanderer? I've had quite a few errors like this but could always solve them by destroying one bad brush...

[Wanderer]

The map would 'twitch' back and forth, and most, if not all, of the misc_models were misplaced on the map, along an x slide.

I destroyed brushes one at a time trying to find the corrupted brush(es), it ended up needing a complete map wipe to get rid of it (and yes, I'm sure it wasn't just the last brush.