First, you have to login using your AkeebaBackup.com account. It's the same one you use on the forum.
Then, go to the top menu Professional Services -> My Downloads. In the new page, click on the "Akeeba Backup 3.0 Alpha" folder. A new page will load and you will see the ZIP file. Click on the download icon towards the right end of the page. The file will download under a mangled name (something like abcdef01234.zip). This is normal. Use this ZIP file to install Akeeba Backup Professional on your site.
Nicholas K. Dionysopoulos
Lead Developer and Director
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