Well seems my last post here has been deleted, why and for what reasons I do not know, however I will supply this comment.
Generally when a game seems "unstable" it is most likely a problem with your computer.
Check your settings such as graphics, drive, etc.
Also do make sure you are not running alot of "hi-poly" content in your game as this may cause unwanted performance if you do not have the gear to run it.
Although I do not run TS2009, I have heard alot about it and my opinion is that it very young, we mustn't expect a child to walk when you tell him/her to! So we must not expect TS2009 to be perfect either, rather we can help by contributing content that we have tested over and over to make sure it is stable.
Auran is trying new things-great things with Trainz, they have been since Pre SP3 Trainz, and look where it has gotten them, yes there have been some rough sections of road, but we have an excellent game, and an even better community.
If that doesn't make TS2009 stable and worth it...I don't know what does!
Cheers and hope you get this figured out soon,
Woody