Minecraft 1.12.2
Occurs with ImmersiveRailroading-1.12.2-forge-1.8.0-7e0f82.jar and using the latest versions of UniversalModCore and TrackAPI
Also occurs with the pre-standalone UMC version, ImmersiveRailroading-1.7.3_1.12.2.jar

Server crashes during the "Loading stock models" portion of startup but does not generate a crash report.

Let me know if I can provide any additional details, it's sparse I know but as I said this crash does not generate a crash report. Only occurs with a dedicated server, singleplayer unaffected.