[1.12.2] Immersive Railroading trains decoupling

[FGBxRamel]

Minecraft Version : 1.12.2

Mohist Version : 1.12.2-320

Operating System : Server runs on Linux, Windows (10+) has the same problem

Concerned mod / plugin : Immersive Railroading; This version but also the ones before

Logs : There are no logs or crash reports.

Steps to Reproduce :

1. Setup a server with Mohist and IR
2. Join and place a train that's a litte longer
3. Start to drive, the speed doesn't matter
4. Stop after a few seconds or minutes
5. See that the train is ripped apart

Description of issue : First up: This doesn't happen on Forge and Magma. The steps are above. We suspect that it has something todo with the chunkloading (or something in the chunks not loading). Usually the trains load the chunks, but that presumably doesn't happen with Mohist, or they are unloaded. We tried all the relevant config files from IR and Mohist, but nothing worked.