I had this problem also, with the carrier hanging up in the rear. I think the push button for the recoil spring acts as a guide to keep the carrier aligned with the rails. If the rear trunnion holes are drilled slightly too high, then the carrier can become misaligned and pop out.
http://armsofamerica.com/polishfbradombrandnew762x39coldhammerforgedbarrelbuyanyv-projectproductpartskitandorqty3andreceive1000offeachbarrel.aspx
on sale $169
yeah, this.
I don't use aftermarket triggers in any of my guns (except the AKT and G2), but now I have seen the light...
I also pre-ordered the akt-e back in march or april... hopefully they push it out soon
I am, it's super short/light. My action got rougher though, compared to my polished G2. I also had to install the safety pin. This is on a polish kit/armory USA receiver
http://armsofamerica.com/polishfbradombrandnew762x39coldhammerforgedbarrelbuyanyv-projectproductpartskitandorqty3andreceive1000offeachbarrel.aspx
Looks like a standard AKM pattern barrel, unlike the ak-601 barrels from k-var.
I would suggest not getting the EZ receiver, sometimes the trunnion holes will not line up with the predilled holes. Also, it won't allow you to adjust where you want to place your trunnion in your receiver.