If you're talking about the ability to Alt+tab out of a fullscreen blitz app (which can cause problems), have a look at this thread:
http://www.blitzbasic.com/Community/posts.php?topic=49055
http://www.blitzbasic.com/Community/posts.php?topic=49055
The forum is locked. These are the original blitzbasic.com forums, kept so they can still be read. No new topics, replies or edits can be made here. To join in, head over to the Blitz3D+ forums.