The Liquid Music and Liquid Rhythm Max for Live (AMXD) plugins — LiquidMusic.amxd and LiquidRhythm.amxd — are installed to the following locations:
macOS:
/Users/<username>/Music/Ableton/User Library/Presets/MIDI Effects/Max MIDI Effect
Windows:
C:\Users\<username>\Documents\Ableton\User Library\Presets\MIDI Effects\Max MIDI Effect
These paths are within the default Ableton User Library directory (on each platform), and should have been automatically created by Ableton Live (8+) at installation.
If you have changed the Ableton User Library to a custom location, you may need to manually install the Liquid Music and Liquid Rhythm Max for Live plugins, by copying them from our backup install location to the appropriate subdirectory of your Ableton User Library path (Max MIDI Effect inside MIDI Effects inside Presets inside User Library).
Alternatively, if you haven't changed this location, you may not have had appropriate permissions to write to the default path when you ran the Liquid Music / Liquid Rhythm installer, and you will similarly have to manually copy-and-paste the plugins. The backup installation locations for the AMXDs are as follows:
macOS:
/Applications/WaveDNA/LiquidMusic.amxd
/Applications/WaveDNA/LiquidRhythm.amxd
Windows:
C:\Program Files\WaveDNA\Liquid Rhythm\LiquidMusic.amxd
C:\Program Files\WaveDNA\Liquid Rhythm\LiquidRhythm.amxd
Versions 1.7.0 and earlier install to the 32-bit location on 64-bit Windows:
C:\Program Files (x86)\WaveDNA\Liquid Rhythm\LiquidMusic.amxd
C:\Program Files (x86)\WaveDNA\Liquid Rhythm\LiquidRhythm.amxd
Depending on the version of Liquid Music or Liquid Rhythm installed, you may only have a single AMXD in this backup location. However, in Liquid Music, the two AMXDs are actually identical, and both allow access to both the harmony tools and the rhythm tools, because you can only have a single instance of either in a Live Set. Thus, when performing the manual install, you can copy-and-paste the single AMXD twice, and ensure the pasted location has one named "LiquidMusic.amxd" and one named "LiquidRhythm.amxd". More info on the manual install process here.