I had a lot of problems with this… I finally got it so I figured I post it.
Here’s what worked for me cacheing maps for DP. First get google earth and install that. Just say yes to all the options. Navigate to the settings in google earth and check off ‘Large’ data cache size '. Now scroll around to the places you want cached. Now go to DP you should see the goggle earth view. [ If you don’t make sure you have selected google earth as you map source for DP in the DP settings under ‘user interface’] Scroll around the map in the same places making sure to zoom in as you would like when using DP.
Now go to the mini app ‘Explorer’ that came with the tablet and navigate to the following
You will now see the folder ‘cache’. Long press and then select ‘copy’
Click the home button then navigate to the following
You will now see the folder ‘cache’. Long press and select 'paste’
It then copied over all the google cache files to the DP cache folder.
That worked for me. I was able to cache by my house and 100 miles away to another place I fly.