If it's dropped again, my bet is he never fixed it the first time, ie they don't usually drop again...
Unless the installer was FENSA registered (unlike mine :( ) it's most likely installed wrong....there isn't much that can go wrong, but the 'toe and heeling' most 'have a go' fitters don't even know about...
My installer keep giving me the 'i've adjusted the hinges story..or i will adjust again etc...' when they basically didn't have a clue....
It wasn't until I carried out research (measurements corner to corner etc) that I figured out what the issue was.....
Really annoying...but I might as well ask one of my Cats if I'm to ask the builder to correct it.....and he's now incommunicardo....as it were..
I'm interested to have a go myself, but don't want to be in the situation of having the replace any snapped beading etc.....just how difficult is it, How To's and write-ups are all very well, but sometimes small-detail is left out.