I was testing another mod:
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2848414313
First I used it in the mode "category only", then removed it, but then added it back later with the mode "passive" to just have the feature of numbering all the road and track types for my convenience, to find them quicker when choosing inside a station or depot construction.
The numbering of available track types inside of some constructions like
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1920437817
was scrambled by the removing and putting back in of that first mod, I had to "repair" those by changing the track type again.
For some reason the maintenance cost of tracks and roads (!) went very high after this, as if the algorithm stumbled upon some weird single very high value and used that as measurement base or such.