fsharp/fsharpbinding — pull request #100 by funnelweb (2013-02-25 12:36:38+00:00)
Title: Use Ctrl-Return for Send-to-Interactive on Mac 

For some reason "Alt-Return" stopped working for "Send to Interactive" in XamarinStudio. Perhaps the keystroke is reserved.

Just switch to use Ctrl-Return instead, which is what is used by Try F#.