Where are all the elements of the app?

I tried opening Garageband, as I needed to do some recording tonight. It was the first time since buying this iMac about a year ago. Well, it got stuck trying to open, showing me this:

Don't know what it was trying to do, but it got stuck. So I thought I'd just download a fresh, and up-to-date version, and install it. Well, I did, all gig and a half, opened it, and saw a pretty blank mixer window, and when I tried to find how to load a song into it, I realized ALL the dropdown menus were grayed out!! Even the Garageband Help menu, nothing at all I could possibly do!

I don't know where all the sound files, loops, instruments, help menu, even the preferences menu is blank. WTF is happening? When I try to click on "Show all topics" under the Help menu, the screen flashes and still does nothing!

Does any one have any idea what is happening here? It's too late to call Support, and I have to work on this recording, and am at a total loss as to where that gig and half that was downloaded is sitting, and why nothing is loaded in the app.... Frustrating's not even the word, at this point...