TheoTown

When I destroy a span of railway and reconnect it, trains won't go through that span of railway anymore, they turn back or turn to another side instead. Can somebody tell me what kind of bug i'm facing an how to fix it ?

You might have used some tram tracks from a plugin or otherwise that use different flags than the trains. Click on the tracks where they are running to find which track to rebuild with.

Same here brother...

Like ABab said, make sure you're using the right rails. Most plug-ins rails use the tram flag, while the vanilla rails use the train flag, meaning that the plug-in and vanilla trains are probably not compatible.