First I created a SF Maintenance form and the only thing I dropped on it was a SF Browse dialog. I set the Search Field to LocationID and then setup the BO using the LocationsBO. I clicked Ok until I was back to the form.... saved it and went back in and the List Population Settings came up blank.
Secondly, I did the same thing with just a standard SF Form... didnt know if there might have been something different between a maintenance form and a standard form.
Hmmm....