I don't think they're the problem either. I have many backups of this route and I went further back with fewer problems. While I can scroll around fine in these versions, driving is still an issue. This was like watching an animated slideshow moving at 6.8 FPS and gave me a nasty headache. I also think the problem existed in some fashion before, but due to the size of the route I never found it because I haven't been in that area or driving the route in a very long time.
In the end, I'm going to the abridged version and I can work with that. I have some ideas of what I can do to fill in the large void this missing area will create, and it is more in tune with the region that I am sort of modeling. In some ways, while this large city area looked nice, it was shoehorned into the route and made to work because I liked the passenger terminals and the freight yards in that area. The rest is packed with buildings upon buildings, as far as the eye can see. I had modified that by removing some areas and replaced those with large hills that I covered with trees and houses, but the overall congestion is too much and I think it is for me too.