Glad you sorted out your issue. I think this is the new 'feature' of Mavericks getting in the way. If this happens again, right-click the app icon and choose "Open". When you invoke it that way, you will have an option to let the application run anyway (it's a checkbox on the warning dialog). Typically you will see this when you install an app from an "unknown source". I think anything downloaded from the internet is considered an unknown source (rather than the app store).
Cheers!