This is great timing. When this came across the forum, I was ready to purchase a couple of those Vinculum chips, thinking they would be easier to deal with than the USBN9604. One more question....

Even if you put the 18F2550/184550 between the vinculum and the PC this happens?

What I am doing with the 9604 is exactly that....
The keyboard plugs in and enumerates with the USBN9604, then as the user inputs keystrokes, this input is sent via microwire signal to the 18f2550, which is then sent to the PC that has enumerated the PIC as a keyboard and handles the PIC as a keyboard. Can you confirm that this is the way that the Vinculum is setup? Don't understand why the PC would be visible to the vinculum at all. Unless, it was in the circuit so that it connected directly to the host.

This is a big help. Thank you for sharing the experience.
--Kirt

Vinculum.... sounds like medicine. Doctor says, "Take two vinculum and call me later today."