I have the same GPS and have finaly found out how to do it. You can only put 2 maps on the GPS at a time or it doesn't work.
If you keep them on your computer and just put the maps you need on the gps 2 at a time your sweet
I have to shoot out soon so I will get back to you with a step by step guide on how to do it..
All you need is the internet your GPS and the cord to plug your GPS into your Computer.
The rest is Gravy (accept waiting for the Maps to download)
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