Dakota 20 - How do you show remaining route distance on dashboard?
Page 19 of the manual states:


  The Trip Computer displays your current speed, average speed, maximum speed, trip odometer, and other helpful statistics. Touch a field to change what is shown in that field.


If you've touched each field and remaining route distance is not an option, then I think it's safe to say that including this information on the dashboard is not possible. That said, the compass mode and possibly the navigation mode seem to be able to include this information, though they may leave off other data that you care about.