I think we can be more helpful guys.
Yes, you will need rather large radii for the zipper to run smoothly. You will also need to panel break the leather. Remember, leather is a sheet good. It can be molded but only very minimally, so it only likes to wrap corners in 2 dimensions and has a thickness of a couple of mm’s depending on the grade, so it doesn’t like tight turns. If the substraight it is mounted to is not radiussed it will also start to wear through.
A little reference, this might be a similar project. A headline cafe my team and I designed for the Definitive Technology Symphony 2 headphones. I recommend purchasing a few things that are similar to what you want to do. Cut them apart and study how they are made. They will also be good references for the factory you use.
