Where is everything installed to?

The installer will place the plugins, presets and other data in these folders.
(This applies to all products released or updated in 2018 )

MAC OS
AU: /Library/Audio/Plug-ins/Components/
VST: /Library/Audio/Plug-ins/VST/
VST3: /Library/Audio/Plug-ins/VST3/
AAX: /Library/Application Support/Avid/Audio/Plug-Ins/
Data: /Users/Shared/AudioThing/

WINDOWS
VST: custom path from installer
VST3: \Program Files\Common Files\VST3\
AAX: \Program Files\Common Files\Avid\Audio\Plug-Ins\
Data: \Users\Public\Public Documents\AudioThing\