First make sure you have gone through this checklist and done the steps on it that you can. Obviously not everything will be the same between Vista and Windows 7 but the latter is based on Vista so most of the same things would apply. I know it was tested by MTU and a couple Beta Testers on Windows 7 but I don't believe any of them were using 64 bit so you may be in uncharted water.
http://www.mtu.com/upgrades/hoster/v...de-hoster4.htm