Here are your definitive answers, all in 1 shot:
1. Light - Bulb is burnt out. Get a ladder, pry off the lens remove old burnt out bulb and replace. You may be able to tell from the bulb what number it is, if not take it to the closest RV store and get help there.
2. Software - (a) Microsoft Streets and Trips 201x (later the better), and (2) AllStays Camp and RV (Android or iOS). The MS Streets and Trips will do your rote planning including overnight stops and using that you can look for campgrounds nearby each stop and verify with AllStays which is quite good.