Are you booting to the Wintech disk or trying to run it from inside Vista?
UAC shouldnt matter if you are booting to the disk. Access to driver not permitted is a problem with authentication not being high enough so if you are trying to authenticate to Wintech with a SafeBoot username that doesnt have "Admin" rights then you will get this error.
I am trying to run Wintech on a normal Vista install with Safebot installed with boot protection disabled (this loads the SB drivers but doesn't encrypt the drives.) The same process works fine on an XP system.
I'm not following what you mean when you say "Authenticate to Wintech".
I'm trying to run SBWintech on a normal Vista Enterprise OS. I support about 50 remote sites and sometimes need to get a quick look at a Safeboot encrypted drive if there's an issue. I can VNC into the remote systems and use SBWintech to view the drive once it's attached via a USB adapter. Right now those remote systems are all XP and SBWintech works fine. It's the Vista systems that are presenting the problem.