Sorry for asking, but are you getting those barriers with other mods installed, or with no mods (apart from the PM files)? I see by your screenshot that you were in Germany near Magdeburg. Perhaps you could post the coords next time you come across those barriers, then I can run some tests. Unless in the meantime you find the cause, or I find some myself
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)