Just watched your overview video and man...that thing is crude. Seriously a welded on scope base riser platform with loose sloppy holes? I don't care how tight you get those bolts, that rail is going to move under recoil with that much slop in those holes.

Upper to lower fit is what it is. First AR I built used a Mega lower with a DPMS upper and it has some slop in it. Not that bad, but enough to make me wedge it.

And a 10+ pound trigger in any rifle is completely unacceptable.

The customer service you got after the sale is the biggest thing though. The way they handed this is just laughable - not in a "haha" way, but rather a "are you fricking kidding me?" way. I'd be spreading the word anywhere and everywhere I can about these folks to make sure someone else doesn't get screwed over by them like you did.

Hopefully the bare bones are at least salvageable once you sort out the rail and get a good trigger in it.