NOTE: The standalone X-Saturator installer provided for the X-Saturator Plug-in Promo 2020 will be unable to mount on OSX 10.11 El Capitan or earlier. Please download SSL Native Complete v6.3 from here, and uncheck all plug-ins except for X-Saturator during installation.
From SSL Native v6.4 onwards, it is not possible to mount the .dmg on OS X El Capitan (10.11) or older, since the build tools do not support it. Apple ended support for OS X El Capitan in September 2018.
To use SSL Native on OS X 10.11 El Capitan or earlier, please install SSL Native v6.3 or older.