I've got two B5.5 wagons. The 2003 GL has one-touch window operation enabled. The 2004 GLS does not, but should. (http://www.edmunds.com/volkswagen/pa...tyle=100377407)
I found this write-up on Passatworld that describes how to do the coding with a "Brand X" device.
I haven't found anything on the Ross-Tech site (including the B5 wiki) nor anything via Google that talks about setting up one touch window operation on B5s. I'd love to be able to use my VCDS to solve this problem.