I only recently started sorting out my own craft room and decided on tall shelves to stock all my quilting and craft books, albums, notions, papercrafting and of course, my fabric.
The other day on going to get a book off one of the shelves I decided it would be nice to have a couple of shelves left for work in progress and fabric I had cut ready to sew, so some things are now piled back on the bed whilst I sort it out into more subsections. Still haven't bought the baskets I was to use as the shop only had two of the ones the I really wanted in stock.
My room isn't big enough to be divided, but would something like the Japanese shoji screens work?
They're light, and light can penetrate through the white/light paper/fabric of the screens. If a sliding door can also be used on runners, then you haven't got the added bulk of having another door that opens wide into the room.
Put the guest bed in the room as you go in, then you can close off your private craft/quilt room at the other end. Unless they're nosey, they have no excuse to get near your work area.