1. A function is planned to allow you to get to the CNavShowRouteModule. Its not possible to get back to it yet.
2. You can't get rid of the different views. You can delete controls off of them and add your own controls to them, but if the function to show the overlay they are on is called, it will show them. Alternatively, you could use the CUserOverlays. Put a button some place in the GPS tracking overlay and bind it to the function to show one of hte CUserOverlays. On that user overlay, you can put a button to cover up the one on the GPS tracking overlay and bind that one to show a different CUserOverlay, then just put controls on the user overlays to show the navigation data you want.
3. This is not really a skinning feature, but I have noted the request.
4. There are a bunch of limitations around the map panel since you can't efficiently show more then 1 map view at once. The map panel also has to be dynamically resized to accomodate the views. Its not possible to allow you to just resize it since it is dynamically resized, but I can add a system metric that will allow you to specify the size it should be resized to.