I have been remiss in not updating the forum. The problem was in fact very simple - the ground fault breaker under the kitchen cabinets. I actually had checked it before, but not very diligently. I believed it unlikely that power would reemain available through the receptacle that actually has the GF (in fact it was tripped) while the unprotected receptacle next to it had no power. A member's insistence on checking these even though they are remote from the problem led me look closer - problem solved.
Second, I found this forum very helpful again just this morning. Last night our DS slide out moved about 8" out, then refused to move any farther out. It was late, so we left it that way overnight. I woke up this morning recalling reading on the forum to check the awning roller above the slide out. I noticed a projection on one end of the roller had slipped enough to catch the bracket. A ladder, screwdriver and two minutes solved the problem. I also had a ladder on hand as a result of reading this forum.
I installed a Tire Minder set from Camping World. It sounded alarm on the Florida turnpike. I pulled over and found a two inch crack leaking air in the left rear Landmark rim. A can of tire sealant and ten minutes with my mini air compressor took us the remaining 60 miles to our destination. As a result, the $219 almost new tire was not damaged at all, the tire minder set is now half paid for on our first trip. I actually purchased the tire minder to help reduce damage to trailer sides from a tire coming apart and beating the trailer.
As to tires, I heard a very rational comment that many blowouts are caused by damaged sidewall cords that sometimes occurs when running over curbs, road debris, etc. Jim, a fellow camper, said some have switched to appropriately rated radial truck tires having steel sidewalls such as those offered by Michelin and have no more blowouts. It seems the steel cord resist breaking better that other materials. He added the trailer seemed to pull smoother (but that is a subjective take). Perhaps some may find this information helpful.
Thanks so much - great forum!