Is CSV export in Studio broken in 2.2.15?

[William]

I'm playing with the Grateful Dead Concerts sample database in 2.2.15 but it won't execute the query unless I select JSON output mode.  Is this a bug or is there something that I'm doing wrong?  All I see is the red box on the bottom of the screen saying the query wasn't executed.  I don't see any extra output on the console where the server is running.

Thanks!

  -William