The stern section looks Ok, it's the frame. Zooming in on your photos, I see that you have put the wrong chocks in. Also you are offsetting the pieces. Each piece or futtock should be directly over the drawing for both A and B side. They fit exactly over their place on the drawing. The line in the chock is the sanding line and should correspond with the sanding line on the pieces each side of the chock, it is not the outside edge, so you have glued the chock meant to go on side B on side A. Every chock has it's own place. Also I didn't say NOT to sand the char at the joints but just be careful not to take too much off that you change the shape of the joint surfaces. You have to clean also the surfaces that butt on to the keel. I have to go out now. Do you want me to go through the make up of a complete frame when I get home later or are you OK with it? This kit is very detailed and so quite complex, certainly the most difficult of the ones I have made. You have to concentrate and have an idea of what you're doing