Reminds me of the early days..
Click link
http://www.vyak.net/forum/viewtopic.php?f=11&t=4446
However, I ended up buying a C-Tug in the end.
Can place it under the centre of gravity, store it in the hatch, and place it upside down on the car's bonnet to easily slide the yak onto the roof racks.
Cheers.