I was helping a Trader get to Worlds End just now...
We had gotten to the river and s/he had pulled out the Raft and began to put it together. For some reason I notice s/he started it on one side then half way through begin to build it on another side of the river edge, picking up the first part (Which held 2 pieces) and then dropping it into the other part (also held two pieces)...
The Raft Failed to appear like normal when 4 parts are put together...