Good News, Bad News and Worse News
The good news is that replacing a fuse in the panel in front compartment on the driver's side worked for lights above sink and couch behind passenger seat. The bad news is that the kitchen table light and light above larger couch are still dark. Could be a mystery switch, as PenJoe suggested. Could be loose wiring, which I will explore when I get it home and have all my tools.
The worse news is that on I-10 Eastbound just into El Paso the air suspension stopped working - but being a newbie and having heard that this particular route was rough, I continued on for several miles until it became too dangerous. Good Sam sent some mechanics who explained that the bouncing on the road probably overloaded the air bags, and the bags have a safety shutoff to avoid over pressure. Whether accurate or not, I don't know, but they re-set a relay switch and everything worked fine for the rest of the day.
The bouncing and banging was severe, and now there is a black corrugated hose (about two inches in diameter) that is hanging somewhat low between the rear axle and the rear end of the rig. There is no obvious missing bracket, and it is about 8-10 inches off the ground with jacks down. Will arrive in Austin, TX tomorrow and want to have a mechanic check that and anything else that might have come loose.
Thank you all for your help, and if anyone knows a good mechanic in Austin, a referral would be much appreciated.