Does section maps support different room sizes with a way to identify entrances and exits?

I'm also looking to do the same thing, using prefab rooms of different sizes. Has this been added? I know you added sections, but they have to be the same grid size right?

It would be awesome to be able to add prefab rooms, with entrances identified in the room grid, and in different sizes. Like a 10x5 room and 4x6 room that would connect their entrances directly or put a corridor between.