I've heard that the new 0-8 and 0-8-1 sub-compact guide rods are a little weaker but I've never used one. I agree with Brad, call Glock. With the unloaded gun, the slide should go into battery while slowly easing the slide forward.
If the little gouge in the frame looks like this, it's normal. It's pretty common in sub-compacts and Gen4's, some have it and some don't. It's not a problem, that area just didn't get filled in with plastic thoroughly, and that plastic isn't structurally important.
