Just replaced the Trigger Reset Spring (HKparts.net #HKPP2032), Firing Pin Block Spring (HKFP101), and the Match Sear Spring (HK45027) on my HK45CT, and while most everything so far is working just fine and the grit is gone from the trigger pull, it'll occasionally hang up during dry fire and not reset.

(youtube) trigger issue

I can't figure out what's causing it. From looking at everything and going back over the guides I was using, everything seems installed properly. It doesn't do it with rapid fire, as the slightest bump will allow it to reset, but if you move the trigger slowly then it hangs up most the time.

(youtube) with slide removed

I'd rather not tear it all apart again, but at this point all I can think of is to take it apart, re-clean it, and put it all back together again.