Hi there, my old man has just brought a boat and it came with a navman tracker 5100, it has a c-MAP card with the new Zealand maps on it. However the old owner said the maps don't load anymore , and the work on the occasion. Just been having a play around with it but not having any luck getting the maps to load it just says device error when going into user card settings, bit of a noob to the whole boating thing so never used a marine Gps before. Have cleaned the contacts etc any suggestions? It was made in NZ so hoping there might be some people who have some knowledge