VST2 :

Place the "Greenland by OVM" VST2 folder in the usual location (for example, Program Files / Common Files / VST2).

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VST3 :

Place the "Greenland by OVM" VST3 folder in the usual location (for example, Program Files / Common Files / VST3).

Place the ‘Greenland by OVM’ VST3 presets folder in Documents / VST3 presets / Overdrive Music. 
By default, the ‘Overdrive Music’ folder does not exist; you must therefore either create it beforehand or launch your digital audio workstation (DAW), which will create it automatically, then close it and place the presets folder in that directory. Then reopen your DAW so that your presets are displayed.