Yikes @sasmstr, I'm sorry about that!
I've added the bug to the bug tracker. We will get it fixed!
In the interim, you can use CMD + J (OS X) or CTRL +J (Win) to show and hide the navigator. Hopefully that cuts down on your frustration a little bit.
Thanks for letting us know, and I'm sorry you had to encounter such an annoying issue on your first day! Please don't hesitate to reach out if you see anything else, or if you need anything. We are always happy to help!