I guess there are always going to be perils in attempting any DIY installtions.
I had considered ordering a system and trying the DIY route, but thought about it a bit more and decided I'd rather spend a few extra dollars on fuel to get to their shop, and let them install it, than be relegated to your situation where you play phone tag with their supprot people, and then have to wait for parts to be sent out, and so on.
Most of the reviews I've read are more about the systems being good, rather than about DIY installation problems. Your story is worthy of note.