I'm doing something wrong

I figured out how to import my sonar data to auto chart and how to create the map, but when I export it to the zero lines card and put the card in my unit, the only thing on the card is a gray line that shows the course I travelled while I was recording the sonar data.

The gray line is your boat track that is still stored on your depthfinder. It is not on your zerolines card.

To get the map to display on your depthfinder, you need to press menu, go to the chart tab, and down where it says 'base layer', change it from 'default' to 'ac'. That should do it.