As per my previous experience with B&T, the instructions were super thorough and easy to follow. The pattern was a little more complicated with the addition of the zipper but if you can insert a zipper you'll be fine. The only modifications I made were to draft a lightening bolt tail and add it at the back of the gusset seam and add ears to the sides of the hood seam.
Well, that's all for now. It was a fun thing to do for Hallowe'en so a win!