Airsoft Canada - G&G F2000 trigger a bit sticky

I'm not referring to the infamous semi-auto trigger problem that these rifles have.

I noticed the battery compartment was a bit small for my needs so I decided to open the rifle's lower receiver and do this modification. http://imgur.com/a/6p5bM#21

It worked fine and I can now fit far larger batteries or even two batteries if I desire. Unfortunately when I put the rifle back together I noticed the trigger was a bit "sticky". It won't fully reset and it comes shy to fully resetting by about a mm. It still fires and I can still operate the rifle normally except one thing, this requires me to pull the trigger out manually to engage the safety. I opened the rifle back up and put it back together a few more times but couldn't find anything wrong. If I put it all back together without anything but the trigger inside of it it works fine.

Additional details about the rifle: I bought it used from a user here on ASC, he says he used it for a year then retired it to being a wall gun for three after that. The only modification I found is that he glued foam and used felt inside parts of the rifle which was done to in order to quiet the rifle a bit but I don't think this would affect things.

tl;dr: opened F2000, didn't lose anything or do anything wrong, now the trigger doesn't fully reset.