When you installed the catch spring detent, did you load the spring first, then the detent on top of the spring?

Is the catch fully moving in the slot without any slot binding?

P mags sometimes have a problem with the follower not being all the way back in the mag to catch the catch tab, and the catch will not fully raise the catch.

Lastly, the when you pull all the way back on the charging handle and put the bolt catch into play, the catch should be rising up in front of the bolt face to retain the bolt there, and not just catching on the bottom of the carrier.  If the bolt catch is only catching the bottom of the carrier, then some thing is amiss on the buffer or recoil spring and either the B/C is not coming back far enough to allow a clean catch, or if the last inch of CH pull is much greater than than the rest last half of the pull, you have either recoil spring coil binding from it being too long, or hammer wedging between the top of the trigger/bottom of the carrier with the tail of the hammer being too long.