Er, which version are you using...? It looks like
, but you're both lacking options on your Background window, and you're missing a number of icons up top.
Well, you should be able to use a background as a tile in whatever version that is. Just go to the room and try to lay down the tiles.
edit: Ohhh, I didn't even think of that. I forgot all about it. Just go to
File, then click on Advanced Mode.