Keyboard Maestro può farlo in diversi modi. Un modo completamente estensibile è creare una sequenza di macro auto-disabilitanti, qualcosa del genere:
Macro: First Command Key
Trigger: Device Key Command Key
Actions:
Disable Macro "First Command Key"
Enable "Second Command Key"
Pause 3 Seconds <- adjust as necessary
Disable Macro "Second Command Key"
Enable Macro "First Command Key"
e poi
Macro: Second Command Key
Trigger: Device Key Command Key
Actions:
Disable Macro "Second Command Key"
Enable "Second Command First Option Key"
Pause 3 Seconds <- adjust as necessary
Disable Macro "Second Command First Option Key"
e poi
Macro: Second Command First Option Key
Trigger: Device Key Option Key
Actions:
Disable Macro "Second Command First Option Key"
Enable "Second Command Second Option Key"
Pause 3 Seconds <- adjust as necessary
Disable Macro "Second Command Second Option Key"
e poi
Macro: Second Command Second Option Key
Trigger: Device Key Option Key
Actions:
Disable Macro "Second Command Second Option Key"
Perform whatever actions desired.
etc
Ci vorranno un paio di minuti per la configurazione, ma puoi configurarlo come preferisci.