: I'm guessing that the flat spot is along the shear line of the hull. You
: should be able to get the deck and hull to meet up pretty good using
: stitches were needed. A narrow putty blade or a razor knife can help in
: the tough areas. If you bevel the edges that will meet on the hull and the
: deck, this will help hold them in the desired position. My hull had some
: wows in it also that came out as I stitched things together. Good luck.

The flat spot, which I had already reduced prior to tacking/filleting/taping by the method described in my reply to Terry Hanson above, was further reduced when I did the final stitching of deck to hull. I did basically re-bevel the edges of the deck-hull joint before I stitched them together -- it happened when I sanded the edges as the kit manual recommends "to give teeth to the epoxy." I made mental notes as to where the earlier beveling seemed slightly off and, when sanding the edges, sanded at a slightly different angle in those areas.

I still ended up with a flat spot even after sanding and stitching tight. It's much shorter than it was before, and the deck "overhang" there is less than it was. I actually pulled out the 2 stitches in that spot and, with my husband trying to hold the flat spot out using the tip of a screwdriver, restitched those 2 wires. But the deck just slipped and popped right over the edge as it had done before. So I decided I will just trim the overhang later, before glassing the outside.