You may need to adjust the lenght to find optimal tune - it's recommended to start with a longish spreader and going towards a shorter one. Sail Construct sail panel templates according to the dimensions in the sail plan. Before cutting your fabric check that the spine lenght of your template is about 110 cm as in the drawing. 9.5 mul def Scaling does not affect to the grid size, it will stay 25 x 25 mm. In the end of template.ps file there is a comment line explaining how to select the pages, which are printed.
Templates are of 'final' size of the panels.
You have to add your favourite seam allowance and fabric for the spine tunnel to the templates. I sew first all left side panels together and right side panels together. Then, taking care of the symmetry, sew them together by making the spine tunnel. The purpose of the spine tunnel is to the keep sail centered and prevent the sliding in tight turns. If you prefer simple solutions, forget the spine tunnel.