Still crashing on startup

[kcs_fan]

Well, here's where I am with the 2012 upgrade:

I still crash during startup on all but one of my custom routes.
The one custom built route that will open has no scenery items, it does have 150 miles of terrain decals all placed edge to edge to form the entire route I want to re-create. I have track laid on a lot of the route but no scenery items at all. Just decals and track.
Any of the routes that came with RW or purchased add-ons will open and run without any problem.
Several on this forum have suggested that I add more RAM to my computer.
My computer guy says 4 gb. of RAM should be sufficient to run the most complicated route I have built.
I upgraded my Nvidea software just in case that made a difference. It did not.
So my question to all of you is this: Should I upgrade my RAM from 4 to 8 gb? Or should I just start all over creating my custom route in TS 2012 after 1400 hours of work?