Battens attached

Now that the sides are attached, the next step is attaching the battens.  The battens are long strips that parallel the keel and support the bottom plywood.  This shows the battens attached. 

It is critical that the battens are flush with the frames so the plywood lays flat on all the defining frames and edges of the boat.  If there are variations it will distort the plywood and create issues when under power.  I think mine is looking good, but only time will tell.  The battens are glued and screwed to each frame.
The battens get real tricky at the front frame. There is a lot of curve and the longest batten also has to twist a bit.  I did not attach the batten to the front frame (frame 4) because its shape needs to be defined by the bottom plywood.
The battens are also kerfed (cutting a slit lengthwise) at the front to permit them to conform to the plywood.  Here is the kerf at the front of the longest batten.

You can also see that the batten doesn't quite fit into the frame.  This is because the hull is curving down at this point. Frames from the rear forward are pretty much in a straight line until frame 4, so that is where it gets interesting.  This batten will be glued and attached when the plywood is attached.  Per suggestions in the instructions, I put a machine screw through the front of the longest batten and anchored a wire to the building form. This allows the batten to be bent down and in to permit fitting the plywood. Once the plywood is attached, the batten is coated in epoxy and released so it fits into its intended position.  This shows how the wire pulls down the batten.

With the battens attached, I can now start attaching the 3/8" plywood to the bottom.