Have you changed the ULT setup from when you had it in the PTP micromag? The PTP mags use a shorter pin than regular mag setups. You may be getting bolt stick issues due to the ULT having too many shims.
Also, check that the ULE body is not bottoming out in the pim hole in the rail. If it does, the body might flex on the rail a bit when you tighten it. The solution would be to file the bottom of the pim on the body until it doesn't touch the bottom of the hole.
I take it that you have had the RT pro sear machined flat on the sides and then drilled out to fit the larger MM/AM pin?
Except for the Automag in front, its usually the man behind the equipment that counts.