Is this the one you purchased?
I just ordered this one last weekend for my PM9. I already have several other Crossbreed holsters. I've tried other appendix carry systems, but not been satisfied. Sorry to hear you're having issues getting comfortable with this holster.
I hope I like this new holster. From previous experience with some of their other holsters, they do take some 'breaking in' to get real comfortable. Looks like shipping time is running a little over two weeks.
I also ordered a new gun belt. My 8 year old Beltman is getting a little worn, although still serviceable. I was going to order another Beltman, but since I was ordering the new holster, I decided to save on the postage and just get the Crossbreed Belt. Hope it does as well as the Beltman.
ETA From the website "The Appendix Carry is designed for popular small to medium firearms". The 30s is sort of getting on up there in size. That might be one other reason you're having issues?
And a persons physical build can also influence the comfort of various carry systems. There's no one perfect holster for everyone. What works well for one person, might not do so well for the next guy. That's why I, and many others, have a drawer full of holsters.
And, last but not least, the old axiom: 'A firearm is supposed to be comforting, not comfortable.' Although some carry systems are a lot more comfortable than others.