I installed my hitch over the new year holiday. It turned into a real pita when I was about to install the cross member (big, heavy thing with the receiver). The top tab on the passenger side had been mis-aligned and only had a partial weld on it!
Fortunately, I had gotten two hitch kits from BMW of San Diego (there for the Holiday Bowl and BMW of SD had $100/off the hitch kits -- friend wanted one too). I zipped over to my friend's house and stole his crossmember and completed the install.
Sent the crossmember back to BMW of SD and they are pulling a new one out of a different kit and sending it to me (so I can replenish my friend's kit).
Soooo, moral of the story is to look over each part of your hitch kit prior to tearing your X5 apart. I'd have been dead in the water if there wasn't a spare kit to take a cross member out of!
Definitely something to look out for. I did take a pic but it is not that good (autofocus went to a distant object...).