Toxic Trashbag

Hello. 1) At the tutorial of stormy seas. In the attached files there are several geo files with different parts of the boat (sails, hull, etc.). In the lesson, the teacher imports and then works with them as a single object. I don't understand how he does it.
2) In the tutorial "beautiful game". About chess and karma. In lesson 4, I have a problem with rendering displacement. It greatly distorts the geometry. I tried, as the teacher said, to reload the render. Did not help.