I went ahead and bought the license upgrade to V9. I have lots of files that are two sided done in the V8.5 format. At first I was working on them like I did in V8.5, by turning off and on components depending on which side I was making toolpaths for. I finally got a chance to watch some more videos and realized that isn't the right way to do it. The components should be on all the time.
The trouble is in V8.5 the procedure was to move the zero plane to the bottom when importing. So now in V9 it thinks my model is double the thickness when I have both sides on. I went into the properties of all the components and drug the base height all the way to the left. It was still to high and I had to go into the properties again, and manually edit the base height value. I am not completely confident that the part is going to turn out the same as it used to. I guess I could run it on some scrap wood and compare, but I was wondering if anyone else has figured out the exact steps needed to convert components set up in V8.5 to V9?