RV Repair: electrical, propane systems, ford chassis

Question
I actually have two questions.  While driving this weekend, I lost all of the running lights on my RV and trailer.  The only lights remaining on outside were my headlights.  I checked all of the fuses including the power distribution box under the hood. I'm out of ideas.  Any thoughts on where I should look next?

My second question has to do with my heater.  When I turn on the thermostat, the blower kicks on but no heat comes through the vents.  I do not hear the ignitor.  All of the propane systems seem to be in working order. Again I have spent hours chasing the problem with no luck.  Any Ideas?

I have a 1995 Shasta Class C Motorhome, It is a 27.5 foot. The van is a 1993. Any assistance would be greatly appreciated. This is the first time I have had any problems with the rig.

Answer
I can almost guarantee you that the fuse that feeds the running/tail lights is blown.  Make sure you are looking at the right fuse.  I once drove from Phoenix to Rapid City in my Class C (98 Winnie, Class C, Ford Chassis)with the same problem, I was reading the owners manual wrong and looking at the wraong fule.Just to make sure, replace it even if it looks good.
You might also have a bad main light switch (dash mount).
Your heater problem is probably either a thermocoupler or the gas line/orafice needs cleaning.