It's pretty rare now to find other musicians active in this community so I hope this effort isn't in vain. Over the years the few I've met have had hard times getting a natural loop (mostly for 2k4). This is a simple process I thought I'd share.
http://www.youtube.com/watch?v=i_L_vS_TKXU
Basics:
Duplicate the loop
Export
Locate the halfway mark
Delete all audio before it
http://www.youtube.com/watch?v=i_L_vS_TKXU
Basics:
Duplicate the loop
Export
Locate the halfway mark
Delete all audio before it