Have you contacted Ruger? Their customer service is absolutely outstanding. Get yourself on the phone with CS and tell them exactly what the issue is, without embellishments, and I'd bet my lunch money Ruger will make it right. If the problem part does not require an FFL, and you demonstrate to the CS rep that you know what you are doing, they will most likely just send you the part you have an issue with.
Well, I wasn't happy with the setup, the TLR-7A is too small for the USP 45, it just doesn't look right, so I tried the TLR-1. After a little bit of file work, it fit's perfectly, is solidly mounted, and looks a lot better.
I am considering selling my UTL along with a safariland level 3 holster specifically made for the USP 45 with a UTL if anyone is interested.