This book is too short to cover everything. It would be neat to add an interior, an anchor, and other details. But there's is still much to cover. So here are a couple of bonuses for your hard work and persistence; a line for the mainsail which you can copy and use for making other lines for the sloop, the door, the portal window, and a nice brass frame.
For your reference, the file
6907_09_Portal and Door Assembly.blend has the file with parts, textures, and instructions in the Text window on how to create the door, and a glass portal window.