I had hoped this would've gone away with patch 1.8.237.1 but alas:

About every other time I hit "Play Vendetta" after the update utility runs, the program goes unresponsive during the NAOS splash screen, which stays up forever.

What OS version are you running? What type of mac is it?

Hmm, did you try the config.ini file? Oh wait, is that for another thing...

OSX v10.7.4
2.6Ghz Intel Core Duo 2 macbook pro (circa late 2007)

FYI this still happens, still ablout 50% of the time, but I can force quit it even in fullscreen mode: command + option + shift + esc for 3 seconds.

I haven't been able to duplicate the problem on our mac mini running 10.6.8.

Does the problem exist if plugins are removed?