You can block mark an area in OSM and save it out, then in the editor bring the files in, add them to one of the menus... and then when you import it will let yuou bring in lots of data which is then represented as line overlays essentially - it varies in its quality and isn't production-ready. The team never use it. Believe it's still there though so... if you can make it work, go for it but don't rely on it too much.
