JDiskReport is damaged, can't be opened

I have tried downloading and running JDiskReport 1.4 a few times now, and after unzipping it and clicking on the executable I get the message:

"JDiskReport" is damaged and can't be opened.  You should move it to the Trash

Why is it not working? I'm running 10.8 Mountain Lion on a MacBook Pro.

Just tried this myself and confirmed that the executable gives the error you mentioned:

"JDiskReport" is damaged and can't be opened. You should move it to the Trash.

I was able to get it to run setup by Ctrl-clicking JDiskReport.app, clicking Show Package Contents and navigating to Contents/Resources/Java/jdskreport-1.4.0.jar. Ctrl-clicking this .jar file will allow you to click Open and bypass Mountain Lion's default 'unidentified developer' error. I did not go completely through Setup (only confirmed that it ran), so try this and let me know how it goes.