There are no lakemaster hd lakes anywhere near me. So, I have a blank zerolines sd card. No time yet to autochart my local lakes. I tried follow the contour by placing the cursor on the shoreline, pressing goto and using 120 ft contour offset. The map selected was 'contour xd' which I am guessing is the zerolines card. Correct? It was the only map that would offer the ftc option upon pressing the goto button. Regardless, this worked great! We fished the shoreline without touching the motor for an hour. Then, a while later I stopped ftc and motored to the opposite shore. When I attempted the same exact ftc sequence listed above the Terrova tried to pull me into the shore! I retried several times but the same problem. Why did ftc work perfectly, then not at all (on the same lake, on the same day)?