The Unarchiver, part 2 (486)

274 Name: Jim : 2012-12-15 15:15 ID:D0Qe62qX [Del]

I bought The Unarchiver and clicked on "install". A grey icon appears on Launchpad with a liitle white dot on what appears to be a progress bar but nothing happens, and clicking on the icon produces no effect. I tried clicking on "install" again and just got a repeat of the previous result. My O.S. is mountain Lion.
What can be done?

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