What are you using to read the OBD codes ?
I bought a cable of a guy in Montreal and used a free tool to read the codes (I think it was EcuExplorer)
As to the VSS, I used a super simple solution, and it seems to work fine. Is your ECU not registering the signal, or is your VSS not sending out a signal ?
Check out page 9 and up:
http://www.vanbran.com/bug/conversion_main.htm
Rob.