I had some trouble with the shell command on this model too, so I proportionally shrunk a duplicate of the outer hull then lofted between the two shapes’ edges to make a solid canoe. I also had to improvise on the railing to; I couldn’t get the fillet command to execute correctly, so I duplicated the two edges, extended them in either direction, lofted them, then extruded them. Those were the only issues I had with this.

 

I also added some paddles, just for fun. 🙂