There have been a few threads lately regarding misaligned and/or poorly operating doors.
One of the common misalignment problems involves the door halves seperating as the door swings thru the 90 deg. position. Enough to disengage. It can be frustrating. A little pressure on the door knob during opening can assure the doors will disengage.
The cure is fairly simple. I explained the technique in another thread, but words don't convey the message all that well. Additionally, the problem addressed in the thread was associated with trailer leveling.
The adjustment, to which I will provide a link, is to pivot the wall "inward", where it attaches to the lower door hinge line. Following adjustment, as the door opens, the swing thru 90 degs is slighly elevated (less seperation from the upper) - problem solved.
Go here to see the adjustment:
http://community.webshots.com/album/551430116XzTzlQ {Updated 6/16/06 @ 2342}
HTH
Denny_A