And that's what I'm doing, sir.
I'll remove unnecessary NPCs that have no really a purpose to be there (non-scripted npcs). By this way I'll to reduce the target NPCs that might have a problem that causes the server crash by doing a list and checking every NPC 1 by 1.
That's ok if they want to be close to global as possible, but I don't. I want the server to work smooth as possible. 8)
Bring me more coffee, sir!
Well I would start with trying the TFS libs, if it works then rescript the ORTS one.
Otherwise you know it's one of the npc files and if you give others the pointers (me included) will help to try and find the issue.