Swap each part separate and see when the problems arise. Just like turok said.
Also, not sure how new you are to building pistols... but it takes a lot more know how than 'throwing shit together' to get it to run properly. often parts are oversized so they can be custom fit. I recently built a 1911 and the hammer was sticking on the Bbh similar to your issue. I know the mechanics of a 1911 and I know the problem was that the hammer wasn't being pushed far enough down by the bbh... I also know that modifying the hammer can screw the whole assembly up... either way I ended up modifying the engagement points between the sear and hammer for a perfect running gun...
My point in all this... you can't just throw upgrade parts into a gun and expect it to be a beast. You often need to file and fit parts to eachother and that requires knowing how they fit.
Again, fit each part one by one and see where the problem is. Best way to learn is through experience! Good luck!