1. Nice ship 2. Scene settings control the sky. If you drag a sky from the library it opens a new file. Go to the scene (right hand menu) and click on scene, then add a sky from the right drop down choices. Play around with it. 3. To add a material to the library, drag it from the materials list on the right into the library under your Users area. I don't have the app with me so I'm going off a sketchy memory.

Never Give Up!