You really should be using heavier BBs, .3's or higher. If you want to stick with the .25s, you need to get the right sized allen wrench. I don't remember what size it is exactly, but it's about the smalled metric size you can get. They come with pinion gears and the like, which is the easiest way to get them.
The screw on the trigger, you do not want to tighten, it mis-aligns the sear so that it won't catch.
Use a really fine grip metal sand paper, and that should take care of your last problem.
The screw on the trigger, you do not want to tighten, it mis-aligns the sear so that it won't catch.
Use a really fine grip metal sand paper, and that should take care of your last problem.