Nicolas-
In case you still need that vi, I might be able to help you. I'm using the T112 boards by IMTEC (grrr) and also looking for working vi's to support mulitple cards.
Anyway, there should be an explanation of the controlling dll's functions in your user's manual. If you can find the GetTimeStamp function there, you can try creating your own vi that uses "Call Library Function Node.vi" to access the dll's functions. This worked for me with antoher function I didn't have.
By the way, have you found someone who still distributes any sort of code for the IMTEC boards? We now only have a very expensive pile of junk here since we upgraded to Windows XP...
Adrian