I only watched the one episode as it was just too painful, but I did see a real 2-6-0 engine as well as the wood mock up. Judge for yourself, both are in the trailer.

http://www.youtube.com/watch?v=0s0JAAfA7IE

Real at 00:18,
Prop at 01:24.

Technical advice in "made for basic cable" is not up to a feature length movie. They just don’t have the money, and I don't think any Hollywood types have put in much manual labor.
The backward ditch digging with a broad ax was at 01:11

The best movie I have seen on the Transcontinental Railroad was part of the American Experience series on PBS. I have not found it online; but I have found it available on DVD:

http://movies.netflix.com/WiMovie/Ameri ... id=2361637

A British series called Seven Wonders of the Ancient World did a fair episode on the Transcontinental Railroad (episode 6.) An outstanding episode was the one on the Great Eastern; built by Isambard Kingdom Brunel, who also engineered the Great Western Railway:

http://documentarystorm.com/seven-wonde ... ial-world/

Episode 4: The Sewer King; was also good; I thought the American ones on the continental Railroad, the Panama Canal, and Hoover Dam were not quite as good. But the Great Eastern, with it's computer annimation, was outstanding.