So in case anyone else is working this out, it was simple once I figured it out. You cannot simply copy your AC folder from one card to another. You have to load your map in Autochart, pull out the original card, pop in the new one, and do the lakemaster update. This creates a new folder with whatever signature or code makes it work. I tried it with a folder copied from my first card and when loaded into my 859 it would say loading chart and then shut the unit down. Now that I have the folder I may be able to move and copy contents within it but for my purposes I will just upload new autochart live data after each trip when I import the files to my PC.

As far as in the unit, from the chart menu, you select the chart card slot you want to use, and then go to map layer and choose AC.