How long was Craig away for?...plus other questions about timeline..

I loved this one, nearly as much as the first......but 2 things about this movie get on my nerves.
1. Brian Dennehy is great in the role as Harrison, BUT hes 20 years younger than Kirk Douglas. In the first movie, Douglas is already showing some age, but in this movie, set some years later, Dennehy is riding a horse across mountains and the country side full pelt. It just does'nt add up. If Douglas was in this role again, he definately would'nt be riding horseback (that fast).

2. How quick were towns built back then? Jim Craig says that the town was built on Spurs property. How long ago did Spur die?? It seems the town was built overnight. I had the impression Craig was gone for 3/4 years, but it sounds more like 7/8 years.

need opinions...?