I had one of those, it was junk out of the box. I took it apart and de-burred and did a lube tune to it, it was 99% better. I later put six of JM's old school buttons on the top rear of the piston, the surface that sees the most force against the action when the gun is cocked, this smoothed the cocking and dramatically improved the latching effort.
That gun now belongs to my brother, it is nearly as accurate as my MM-B26 and it is much more powerful. I really think it is as accurate as the B26, but is a little more difficult to shoot.
If you have the adjustable trigger, that is the stuff. I took my trigger apart and polished the mating surfaces too, I'm not sure what else you could want from a trigger, that thing is great.
One other thing to look for, the trigger assembly kind of "floats" on the pins in the action, it can be slightly cocked or off center contributing to your issue.