Yeah - my Gamo is pretty bad- and no way to alleviate that I can see.
I don't know which model you have but my GAMO had a horrible trigger. According to the box it came in, the trigger pull is adjustable. Damned if I can remember how I did it but it's now right around three pounds and lets off very nicely. I'll have to see if I can find the instruction book. I'm guessing it's somewhere out in my shed as that's where it was when I finally figured out how to make the adjustment.
On hunting rifles, both the Browning BLR and B78 took a bit of getting used to but now they're useable if not perfect.
Paul B.