[neomaximus2k2]

weird, i have been to this area also but have yet to find any bugs within it,
this is normally caused by NPC server lag, basicly the level can not load the gmap to set the tile heights, so it simply sets it to the sand, hence the reason it looks flat, when you reconnected it would have forced the gmap back on.

If you still have the problem then raise the issue again, Hope this posting helped solve your problem