Lots of good ideas - french cleats are a nice, simple way to hang heavy stuff on the wall.

After a LOT of mucking around, I just couldn't get in touch with the manufacturer (they don't answer their phones, emails or faxes) and my local tradelink didn't have an answer. I asked the tradelink to get the info for me.... (they couldn't get in touch with the manufacturer either!). SO, tradelink got one of their preferred plumbing contractors to help us out.

He said that he installs these cabinets a lot, and he uses 7.5mm roofing screws (odd, but he said they're easy to drill thru the back of the cabinet & have a large head to prevent damage). He said he just uses 4 along the very top edge of the cabinet, and 2 in the bottom. Then he puts the sink top on with silicon. If he's installing one by himself, he screws a timber support on the wall under the cabinet to hold it in place.

Sounds reasonable, and fairly similiar to some of your suggestions. Now I just have to get around to demolishing our existing cabinet and hauling the new one in