I installed a map (A-Z Greater Manchester) and it appeared on Memory Map on my PC successfully. Two days later it has disappeared for no apparent reason. What happened, and is it possible to reinstal it? Also, I sent it to my ADV2800 and large parts of the map are missing. How do I correct this, and is it possible to delete unwanted maps from the device?

Have you downloaded the full map? (The program will only download the portion it needs to show you the current location and zoom level.) The best thing is to open a location you want and select MAP > DIGITAL MAP SHOP > ACTIVATE VISIBLE MAP to download the full detail for that location.