Ok, we let our users save layouts and we have found that if you unpin a pane and let it slide in then save the layout. Then close the app restart it and load the saved xml layout file the pane is in its original pinned position. Is there anything we need to do inorder to make sure the saved layout truely represents the layout you want with unpinned panes.
This sounds like it may be a bug. I would recommend submitting the issue to the support group: http://www.infragistics.com/gethelp.