Download your copy of Ultra Fractal 5 here:
After installing, Ultra Fractal will run as a free trial version for 30 days. If you already have purchased a license key, simply enter it when Ultra Fractal starts to unlock full functionality.
Installation (Mac OS X)
To install Ultra Fractal, simply drag it from the downloaded disk image to the Applications folder on your Mac. To start it, click the Spotlight search icon at the top-right end of the menu bar, type 'Ultra Fractal' and click the application icon that appears. Alternatively, you can locate it in the Applications folder, use Lion's Launcher, or pin it to the Dock so the icon is always available.