Airsoft Canada - Need a saviour for my Inokatsu M4

I've had this thing for a year and a half and have never been able to use it.

I fired it at home for a few mags and it seemed to work fine, so gamed it once it got warm enough. It worked well for a few shots until the bolt broke. Since then, I've replaced the bolt with a RA-Tech bolt, and it constantly breaks nozzles after a few shots, even the aluminum ones. And this is regardless of the BBs I use. Seems to work dry-fired, but as soon as BBs are put in, the nozzle breaks after a few shots.

I bought a RA-Tech chamber, thinking the stock one was the problem, but for the life of me, I can't figure out how this thing works or is supposed to be installed. I've had the stock one apart, but this replacement one just doesn't fit. I've tried everything I can think of with this gun and can't get the damn thing working right.

Bottom line is I suck at working on gas guns. I need someone with experience with these things that can help me out and get this thing working properly so I can either use or sell it (probably would keep it if it worked). Willing to pay whatever it costs to get it working. I've already got $2800 into this thing, so I would love to be able to use it.

EDIT: Also, I removed the rail when I took the front end off to remove the barrel and get the hopup out. And for the life of me, I can't get the damn thing back on, so that's something else that needs to be done. Also have a brand new WA mag that leaks like a sieve from the main outflow valve. Would love to get that repaired as well.