I can't understand the drawings either . And damp lucky if I even turn up friday let alone stay to the end .
The fact he is cheaper than all the big companies makes it pretty obvious he's a small operation, bigger the company, bigger overheads, higher price...
I think in short you were BOTH in the wrong.
This I agree with. The "Not impressed", would have been enough to get my back up.
Moving forward though, I used Paul Roose to do my custom hoses and cannot fault the service or product. Instead of complicated drawings which can get lost in translation I just bent up some 15mm copper and sent him that. Far less likely to be disappointed that way.