Called Apple Care today.
They asked where I was, I said nyc
They said to try a more remote location because in cities, the internet is not pure enough and the down loads get polluted by a cache
I'd never heard such nonsense in my life, but sure enough, I found myself in the country today, so I attempted download and it worked perfectly.
I cannot believe Mainstage cannot be downloaded in a city.
Apple is now a rural only company ????
I live in rural Kentucky! And it still didn't work. My internet connection is cellular, but it's very fast and reliable. I have a data limit on my plan (there is NO unlimited option), and I have used up my limit trying to download the stupid "Basic Content" that shows up at the end of the download. So frustrating!
It looks like the program downloaded fine, but hangs on that basic content thing. ugh.
Thanks for the reply, good luck to you.
<Email Edited by Host>
I think the issue is that, according to Apple, unless your internet connection is lightning fast and completely pure, it will always corrupt during the Basic Content load.
My actual app always loaded like you, so I would recommend going to a friends' house who has a fast cable connection and try again.
I lost days over this, so I feel your frustration.
A simple disclaimer from Apple would have been the civilized thing to do.