Originally posted by JTRipper
Not to dig up old bones, but I found a copy of UT Package Tool a week or so after my last post in that troubleshooting thread. I hadn't deleted your map yet, so I said "what the heck" and tried it - it opened your map, and it did find a levelinfo. There was a problem, no doubt, and maybe there was something wrong with the levelinfo, but it looked ok in UTPT.
A rather odd bug that I've only run across once is brushes that won't delete. A mapper on my team started having them, and finally figured out that the ones that wouldn't delete were ones that he had duplicated. A look in the search for actors browser showed that each of the problem brushes was listed twice. I exported the level to T3D and opened it in wordpad to have a look - the affected brushes were all listed twice. The delete flag was getting set when you tried to delete the brush, but apparently on the cleanup pass it was finding the brush that hadn't been marked for deletion and moving on to the next actor.
Duplicated brushes also sometimes develop errors - vertices become "unjoined" or duplicated, or new edges pop into existence.