So I randomly swam around and by some stroke of dumb luck found the giant raft. As I was like, 1 minute away from hopping on to it it suddenly disappeared, along with the nearby island behind it. Uhhh.....
I just had this same issue. I didn't explore it as deeply, but I did try to build a new raft (to no avail, nothing to build off of). Not sure how big the map is and how feasible it is to swim to my old raft.
