It sounds like you've done your homework about the differences in the devices!
There's an open source program to control the minipro boxes. You can probably add the changes you've discovered for the PIC16F1938?to it easily and do yourself and everyone else a favor!
I use this program on Macintosh and linux all the time and it works very well for what's supported (currently roughly the same things as the programmer's official software).
I found that the original programming that came in my ATU-100 kit (the locked one from Malahit) actually did what I wanted with my 5W QRP rigs with no changes - I stopped trying to find a way to reprogram mine for now.
just a few thoughts....
M
AE0GL
