Yeah, those errors are cryptic at best.
Try from the launch windows, go to Settings, add a check for the "LogMate" option, then run RailWorks.
This will usually give you a more intelligible readout of any errors and such.
Sometimes an error like that could have to do with a missing or bad asset. But then again, I'm no expert with RailWorks, so it could be just about anything.
A friend of mine who was building his own route recently had similar errors to what you had, and he think it had to do in part to a "turntable" he had added, as once he removed it his route would load in again. I think he used "RW_Tools" to remove the problematic assets/ items. A great utility definitely recommended for people getting into the route and scenario building side of things. You can also use RW_Tools to help track down problems and remove or replace assets.
http://www.rstools.info/rw_tools.html