Can I mark a location as a "Favourite" without inputting an address? My sister lives in a remote lakeside cottage, and I'd like to list her home as a favourite in the Nav system, but her address is misidentified on her rural road -- the road is listed, but her house number isn't in the actual location of her house. Because I want to set my Sentry to turn off at "Favourites", I really want to have the actual location. What can I do?