I really am sorry to be a pain in the butt, but I'll outline what I've done.
1). Paired my Hermes up with my TomTom 910.
2). Run the .cab.
3). Soft reset.
4). Copied the files into the Windows directory of my Hermes via the storage card.
5). Soft reset.
6). Repaired my Hermes and TomTom 910 after having deleted the previous connection. At this point it says "The following features were found: Hands-free calling, Wireless data connection, Phonebook".
At this point I try and setup a data connection that it hits the fan. It's really annoying because it feels like I'm falling at the final hurdle. I also wondered if I was struggling because of an issue with connecting to the T-Mobile network, however am I right in thinking that mccreath's using a T-Mobile GPRS contract SIM connection?