I have some pictures of my rack in place....
It shows where the feet fit. Perhaps Thule are being overly cautious by saying not suitable for glass roofs on their website.
It takes 3 bikes easily. A good website for bits is
snowchains.co.uk - Weissenfels snow chains to buy or rent
They have a phone number and are very helpful (where I got all my thule stuff from). You can collect Mon - Fri, but looking at your location, their delivery might be the best option!!