JDW,
It takes a lot of moxy to own a traveling home, and more than just a little patience. My second motorhome, from a dealer, with Cummins factory support locally, literally spent more time in the shops of the two the first year than I had use of the unit. Turns out the engine problem was a sensor that reported low air temp to the engine computer below 50°F and reset itself above that but still had a check engine light til it warmed up. Took a year to find the "problem": Cummins never did, I found it with a can of freeze spray. Why couldn't cummins find it? My answer would be lack of experience with their own product.
That was just one of the problems in year one. All in all, it was a unit we had a ball traveling in and there are days that I wish................
I know you will "eventually" iron out the problems and have a good run with your unit.
Good luck,
L. G.
P.S. In that unit the kitchen was on a slide and NEVER solved the potential to leak drain water because of lousy design, just replaced hoses that had to move with the slide every six months or so.