Im a 7x64 user also.
First attempt of virus 5.0 install: right after the dialogue box 'connect and turn on vrius' it wanted to install a driver clicked okay - blue screen...
Reboot try again (whilst not having a shit load of stuff running behind) I get the rollback stuff... Uninstall previous version try again, rollback. Attempt to uninstall drivers manually from device manager then try again same thing rollback...
Am now installing 4.5 what I previously had and thats going fine, so seems there's deffo something in this public beta of OS5 thats not fully compatible with alot of peoples win7 x64 setups. Will now be waiting until they release a new version.
P.S Im running am older virus TI 1 Keyboard aswell by the way.