Interface to User Logic and DMA...

For something like this, I've always had to fall back on custom logic driving the waitrequest line to the IUL.

The only other thing I can think of is creating the IUL, then editing the system.ptf file (not sure that would work, though) or creating a custom component type (based on the IUL-generated module). There are a lot of settings in the PTF files that you can't get to from the IUL GUI. As I'm still learning how to do just that, I'm afraid I can't be of more help.