Steam Can Anyone Explain Why I Cant Set A Path?

It doesn't let me set a path for some weird reason.

 

I am unaware of any issues regard setting paths; I am sure someone with more knowledge about Free Roam will be along shortly to clear that side up.

Where were you when you were setting the path, and where were you setting it to?

 

Are you in the drivers seat?

 

I have also toyed with this and it seems like distance is a factor
For example...Look at the letter "U" you start on the left or right side of it, as I was setting the Go via when I got near the bottom of "U" I was unable to set the Go via, but when I got to the other side of the "U" I was able to set the Go via and Path, well the Destination Path needed to be set first, but also setting the Path I found also looks at the track you are on and where you want to end up. If let's say you have 4 to 6 tracks and there are crossovers that you the player can't control that does affect on how the path is set.

 

Sometimes there are destination(s) you can't reach from your current departure point. Try to reach something on the "left" in Frankfurt Hbf for example - you have to go near there first (like where the two 216 stand and wait) and then set the path to the final destination. Like shunting ;-)

 

Wait, I'm stupid. I just realised that that message comes up when you click on the train, rather than when you click on the place you want to put the marker.

Were you sitting in the driver's seat of the train that you clicked on?

 

Yea you need to be sat in the drivers seat of the train you want to set a path for. If a location is not reachable then it will say so when you try to set the destination.
Also when you take over a ai service I don't think you can set a new path either.