Lol .. a shameless plug there GM9
Actualy I have had the same problem before and the only thing that fixed it was deleteing the char settings file... and that happend quite a while back not just recently I might add.. And at the time I was switching UI's other than my own, to try them first hand rather than look at code and pictures, When I reverted back to default and also my own I lost the maintained window.. I think maybe it just could happen from doing that in rare cases...
Either way deleting the char settings file sorted the problem for me at least.