ok, i got it to work now. TBH I think it was working all the time :/
I had tried it with geometry, but i was just using default lighting so I couldnt see the change. Also, while the value was selected in the channel box it didnt change. As that's where I was looking, and the values were selected it all resulted in me thinking it didnt work.
I feel most sorry for the guy I bugged in IRC the other day.
Oh well, thanks for all the help. Another lesson learned.
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