I have navionics and am still trying to figure it out,this will be my 2nd time using the map like it so far . What part of May are you going down there? I will be down there this weekend for the second trip this year,I fish Twain more then I do here in Iowa. Are you by chance going to the Twain camp out at the end of May? My fishing partner and I will be there,this will be my first group camp.Looking forward to meeting all the cdc members. Jim