I'm not able to get a negative inset on the doors/drawers on the attached cabinet. I'm trying to get a 1/16" gap but it gives me a positive overlap every time. A couple of times the program has reset the insets to 0 while I was changin them. Is it the program or just user error?
Unless I'm misunderstanding what you're attempting, the inset should be a positive 1/16 rather than negative.
I opened your assembly and edited the doors of the base cabinet and was able to get the 1/16 gap.
When you change the inset for the doors to 3/4", the description changes to gaps. The gap value is entered as a positive value, not a negative, if you want a 1/16" gap all around the doors and drawer fronts.