I am creating a little arch, a child’s toy, in Blender. I started with a cube, stretched it. Then I went to object mode and created a cylinder. I plece the cylinder in the middle of the box, and used a boolean modifyier to subtract out an arch. Everything looked good, so I deleted the cylinder, and marked some seams on the toy arch. When I unwrapped I found a lot of wierdness and extra geometry. What did I do wrong, and how can I clean this up?