Rotation is not a problem, they seem to be properly aligned to a 90? axis, and from there on simply righting them N, E, W and S makes them OK for the buildings (all buildings in the city have right angles aligned to the 4 main directions, except for a small part of the church and the Tower of the Magi).
What I need is an exact proportion of all parts to each other and if possible, they should be working w/o scaling (I mean the -a- and -p- parts that get attached sideways). If I i.e. put a standard side roof piece, it should be 128 pixels high in the game, 64 pixels wide at the base, and either 64 or 128 or 256 pixels long (if you could make different models, the longer ones are to cut the total polygon count on the map, making it faster to render). The side corner pieces should be 128 high and 64x64 at the base (width/length).
Also, there is some kind of base point in all models that determines where exactly they appear in the map when I put down a single point in WadAuthor for the object. This should be at the outer edge of the object (if it's on the inner edge, all object rest directly on a linedef and that makes WadAuthor build nodes all the time which takes a lot of extra time, and most probably slows the map tremendously). With corner pieces it's clearly the lowest outmost point of the object, with side pieces best would be the outmost lowest middle point (or if it's easier to do than one of the outer corner points).
Now as to the other type of roofs (roof1.md2 and roof2.md2). The most important would be that their anchor point or base point or whatever it's called should be at the lowest point of the object, at one of the edges, right below the middle spine (where it's highest). If you have control over actual object sizes and proportions, it'd be cool if it'd be 256x256 (XY), that can be scaled in-game to allow for smaller or larger roofs.