It seems to be fixed in that test version
I havent played a lot with it yet (its early morning

) but I replaced my station with it and moved around and the bug did not show up.
I doubt a savegame would help very much, you probably wouldnt be able to load it; I use latest nightly with six patches applied to it, so you would probably need my OTTD version to load the savegame too

(station supplies, daylenght, build & refit, distant join stations, middle stop and cityrating patches).
So I think you managed to fix it, but when I get to play it a bit more, I will focus on building some steelmill stations here and there and see if the problem occurs again.
Anyways, I still love the work you're all doing with this, and this little tiny bug would never stop me from using this
AWESOME station set! Also I'm kinda sorry to 'ruin' the release with this bugreport, kinda feels wrong, but it had to be done
