Well as a temporary fix we ended up putting some 3M step tape on the drive roller to give it some grip. It worked out just fine. I think if we can ever get the new canvas broken in things will be fine. We cut a few acres of beans today after church and the tape seemed to cure our problem.
The new canvas it plenty tight. The manual warn about having less than 1" of sag. We did cut slits in the new one just like the old canvas had. Putting it on and tightening it up really was not that big of a deal. It was a touch too wide. We had to cut off about 1/4 of an inch or so to make it narrow enough to run in its track.