i had similar problem with error on background shoreline that i drew then imported as the lakemaster shoreline was innacurate
...called support,,
and i ended up deleting the AC file from the zerolines card and starting all over with new data/map on zerolines card
from what i can see u can edit data on the pc with in the program but once its written to the card i dont think u can edit it??
perhaps greg or somenone else can chime in with comments
DS