I practiced using the KO2, (EP-133).
This is a helpful note for scale selection

Orca

Orca is a midi sequencing environment.
I learned by following this video

Hotkeys

CTRL + , : Next Midi Input Device.
CRTL + . : Next Midi Output Device.
CTRL + SHIFT + M : Refresh Midi Devices

Symbols

[bpm: .TEMPO] > sets the bpm to a value to the right.
[.x D .y] > puts out a BANG every x/y frames
[: .NOTE] > sends a midi note to controller
[.l T]> Creates a tracker of "l" length
[.s C .l] > Creates a counter that counts up every s frames to a maximum of l