Sw m&p 40 gen 1 - CAA Micro Conversion Kit for Smith & Wesson M&P 9/40/M2.0

I got online and ordered this set up for my gen 1 sw m&p 40, when I received this unit, I installed my 40 in this unit, it snapped into place great, but the back hatch door would not close, after reading up on the paper work sent, found out they sent me a gen 2, all I needed was a replacement for hatch for a gen 1, small little piece, could not have been more than 5 or 10 dollars , which I would have gladly paid for, I emailed them, took them awhile to email me back, so I called, the distributor said they would contact the manufacturer to try and resolve the problem, got an email finally that said cant send you the part, just box it up and send it back, not gonna do that, I'm a pretty good fabricator, so I'm gonna cut out the knotch on the door that's holding it off of the gun,wanted it to be factory but guess I'll deal with it, I made sure 3 or 4 differnt times that it was the gen 1 that I ordered , still received the wrong one, not happy with how they handled it, was gonna order more stuff from them, not to sure now, to many other manufacturers to choose from to deal with this