The visual distinction between enabled and disabled buttons for play, etc. is too subtle. I can't tell if they are enabled until I try to click them.

Buttons are greyed out. Isn't that enough? Looks good here (linux & mac).

But active is also grey. :P It took me some time to notice how much grey means "active". Maybe it would be enough to make the distinction larger? Like make the disabled state even less opaque than it is now? Maybe I am the only one that finds it hard to tell though... :)

Screenshots: http://i.imgur.com/IQlXjvB.png http://i.imgur.com/jqQ9hmZ.png http://i.imgur.com/1G7gcTI.png http://i.imgur.com/wEM4BqQ.png Darrin, Ryan mentioned that when we start using the app manager, we don't know that the greyed buttons are disabled and expect them to work (which becomes clear only when they eventually get enabled). What can we do?

I consider this as a WFM. Nobody else complained, and my eyes tell me it's good enough :)