Two more items.  Installing content to a runtime and adding a figures and props to a scene.  Most new users have no idea how to install content or where.  If they learn to install it right the first time, it saves them a whole lot of grief later.

As for the second, I've lost count of the number of new users who ask how to import a figure into either Poser or DS.  They don't understand the basics of adding a figure to a scene or the Poser library.

Render settings is another.  How many bounces, irradiance caching, when to use IDL, min shading rate.