Keyboard Maestro puede hacer esto de varias maneras. Una forma totalmente extensible es hacer una secuencia de macros auto deshabilitadas, algo como esto:
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"
y luego
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"
y luego
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"
y luego
Macro: Second Command Second Option Key
Trigger: Device Key Option Key
Actions:
Disable Macro "Second Command Second Option Key"
Perform whatever actions desired.
etc
La configuración tardará un par de minutos, pero puedes configurarlo de la forma que quieras.