When trying to open "Art of illusions.app" I get the following message under OSX Yosemite.
“Art of Illusion.app” is damaged and can’t be opened. You should eject the disk image.
Safari downloaded this disk image today at 9:27 PM from prdownloads.sourceforge.net.
If I open the "ArtOfIllusion.jar" with Jar Launcher.app (default) (15.0.0), everything seems to work fine.
I downloaded the disk image twice. Both with the same result.