YOLO is a brand name, so there is no converting another brand board into a YOLO, to be technical. From what I understand, the YOLO board is much lighter than a windsurfer board, but stability will likely be fairly similar, or better with the YOLO. The YOLO isn't designed for cutting like the windsurfer.
Go check out the race tonight, mentioned by Kurt. Get there a little early because many of the racers will be warming up on the boards. I understand that YOLO just received a new shipment of boards, so maybe they will have some reserved just for people wanting to try them out. Gulf should be flat this evening, so it should be a perfect day for a the first YOLO board race in the Gulf.
