: i have similar problems all the time, does that mean there are corrupted maps
: on my hard drive?
: point two I sometimes get a bug where the levels switch from one map file to
: another.
Most likely. Try downloading a fresh copy of the map file from bungie.org's Trilogy page.
As for your other problem, are you playing Aleph One, with other scenarios on your hard drive? Sometimes, AO can get confused about which map file it's using, so before you play you should go to the preferences dialog and select the map file that it lists in the pull-down menu, to just to remind it of which map file its supposed to use.