Installing windows in living room slide-out

There wont be opening framed for the window so there's a distinct chance the corners will crack outward depending on how big a hole you make. Also, make sure there isn't a "stud" in that location - you don't want to cut one.
If you go through with this then I suggest you use a very small window with radiused corners. These window usually slide up and down as opposed to opening outward to keep accidents fro happening.
They will make a very nice addition to the slide though. I can't imagine not having them!