I've been happily playing away on a fairly large map with an ever increasingly integrated rail network. This series of "WTF" moments have started only in the last hour. Noticed it upon adding another regional line to the rail network. However, this problem is beginning to effect the ENTIRE network.

As is my practice I use path signals. Often one way path signals. (I have a hard time wrapping my head around the classes of block signals.)

Problems in the order I noticed them.

1) Added passenger trunk line with terminus station to the new division. Upon assigning orders to this trunk line train that intersects with a main line hub station, the train went off down the trunk but at the last signal before the station came to a stop. "Waiting for free path."

There was no train or obstruction between it and the terminus station. I double checked my path signals. Triple checked. Exactly how I always but signals at a terminus. Path signal (normal) facing the exit of the station. My other terminus stations are operating fine.

I fiddle with it for a while but cannot get it to go to the station. Got it to go way off route though. Upon making all orders non-stop to hopefully get it home, it just started going willy-nilly across my network. Eventually had to shutter it away in a depot for now. Odd.

2) New oil freight long distance across my map exhibits the same behavior with a different new station. Again, nothing has changed in my terminus station construction habits. I've triple checked for errors of signal direction, etc. I have passenger terminus stations operating fine this way. I have MANY freight terminus stations operating fine. Just the new ones wont co-operate.

3) Trying to get this large oil train off the mainline it was blocking, suddenly noticed the pre-existing freight terminus stations near it started exhibiting the same behavior in their trains. All these stations have been set and left to run without problem for 60 game years. Suddenly none of my terminus freight operations in this corner of the map are working.

4) Horror of horror my lost choo choos are starting to randomly reverse in their tracks. Caught a few doing this on the boundaries of some one way path signals and started to head back at oncoming trains behind them. Stopped a few in time.

Then one of my prized coal trains jumped a one way signal at the same time this confounded new oil train decided to reverse itself. Booooom.

At this point I've saved and just stopped playing. I'm currently wondering if I just found and tripped some bug, some cascading failure of the YAPF algorithm and soon all my trains will be crashing into each other.

It was strange enough that new trains wouldn't work right. But to suddenly have old trains, like that coal train that's been working perfectly on that heavy freight sector for something like 110 game years to suddenly just flip the f out, refuse to go to its coal mine, jump a signal, and get wrekt?? That's not normal game behavior.

So, I'm at a loss. What the Hell do I do now? [shrug of complete bafflement]