Hi Jan & Mike,
No need to worry about where the radiators are fitted - there aren't any!! I have put 2 full size beds in the room, there isn't much room between the ends of the beds and the wall, but enough to pass. I tried them lengthways, but felt the gap in between wasn't enough - couldn't even fit a small bedside table. If you get narrower beds i would say that lengthways is better - normal size beds will need to go across the room, you can have reasonable space in between - just tight at the end.