QUOTE(LUBA @ Sep 20 2006, 05:29 PM)

I see so your saying you can have only one downloaded map at a time. If thats true it blows! Yes I loaded topo first then CN.
You can upload maps from both Topo and CN at the same time...in Mapsource use the Map Tool to pick the maps you want from Topo then on the drop down list switch over to CN then pick the maps you want from CN...when you have all the maps selected from both Topo and CN upload the combined mapset.
Like I said before: "Note that if you uploaded maps from TOPO and CNav for the
same area one will cover the other and I think CN has priority over Topo...so you won't see any topo maps."
Your dealer is right...there should be a toggle to turn installed maps off and on....example...if you uploaded maps from Topo and CN for the same area CN will cover Topo so you would have to toggle the CN maps off in order to see Topo and if you toggled Topo off you would see the base map....and you can even toggle the base map off for a blank screen.