However, this requires to re-adjust the type of nearly every road tile on the map, as there are "leftovers" from older NewGRFs, for example the internal road types of Polroad, which I decided to switch off, since they cause a lot of trouble.
Generally, I found the combination of OTTD 13.4 and U&Ratt 1.1 to be very "forgiving" and did not manage to crash the program so far besides trying hard
However, in that context, I noticed an unexpected behaviour of the "magic bulldozer": outside of cities, it is easy to convert old road types to the new ones. However, some cities with low rankings don't allow the road types to be changed while those with favorable rating always do.
Now, if I select the "magic bulldozer" and don't bulldoze anything with the "bomb icon" but instead select "convert/upgrade", I can change the road type "against the will of the city".
In previous games, I always bulldozed and then built road tiles new, which was a problem with roadstops, since if the rating is bad, you cannot build a new one, but with the approach above, you can "upgrade over" the road stop.
Is this an intended behaviour or some kind of bug?
And if it is a bug - it is a very useful one to me, so please don't fixed it