The axle installer is a standard Mac package file. axle is a webserver application and is installed in /Library/WebServer/documents/axle, so once the installer completes you won't need to drag an application into your Applications folder, as you would in the case of a typical app. It only needs to be installed on the Mac acting as your media management server, since all the other Macs and PCs in your network (as well as mobile devices) will access it via their standard web browsers.
Please ensure before you install axle that you are logged in as a user the server can have active at all times, as axle will not function unless the active user is the user who installed axle. This user must have administrative privileges.
Launch the installation package file to begin the installation. Click continue to advance through the steps of the installation process, and enter your password when prompted. After the installer finishes copying and setting up all required files, it will create the necessary database tables and entries. After axle is finished installing, it will prompt you to restart your computer.