Thanks, Ray. This is very helpful.
I am getting big images (17MB) but I did check 1/2 subframe and Auto Dark Subtract was unchecked. The computer itself is very fast (6-core Xeon processor at 2.7GHz) but I'll add time for the solution set.
I'm surprised at the need for the USNO A2.0 (I do have it downloaded) given the focal length and thought the GSC11 would be enough. But I'll try USNO A2.0 tonight.
Pixel scale is off for sure: closer to 0.9 than 1.6. (3.76 pixel and 819mm) so I'll make that correction.
As for #3 (Recal Near Zenith at Start) my dome shutter configuration made that difficult so I gave up on that. When it moves to that position the telescope is on the same side of the mount as the unopened part of the shutter. So even though the shutter is open past zenith it still blocks about 1/2 of image. If I rotate the dome 180 degrees it would work. (Ironically, I got a good solution at one point at zenith even though the telescope was partially blocked.)
I'll check everything else and give it a try. Many thanks.