I've heard of this happening before, what revision is your 995? There should be a letter in the serial number. Some of the older ones I think would allow the trigger reset bar to slide over the top of the trigger cross bar instead of pushing it down.
the ATI may alos be causing you problems as well. a few other users have reported trigger problems once the ATI is installed. look for any casting flash or other obstruction around the trigger group and associated parts.