The User Action Buttons are in the settings.ini in the Chord Picker install folder, open with Notepad.
You have the button name: ButtonCA11name=Unfold
and the button function: ButtonCA11funct=!{e},{Down 10},{Right},{Down 5},{Enter}
so it sends Alt+e to open the Edit menu
goes down 10
then right
down 5 and hits enter.

http://xahlee.info/mswin/autohotkey_key_notations.html

Quote:
[BiabVersionSet]
key=2016_later
[CustomActionButtons1]
ButtonCA11name=Unfold
ButtonCA12name=Freeze All
ButtonCA13name=UnFreeze All
ButtonCA14name=Output Chords
ButtonCA15name=ERROR
ButtonCA16name=ERROR
ButtonCA17name=ERROR
ButtonCA18name=Jazz Up Chords
ButtonCA19name=Jazz Down Chords
ButtonCA110name=ERROR
ButtonCA111name=ERROR
ButtonCA112name=ERROR
ButtonCA113name=ERROR
ButtonCA114name=ERROR
ButtonCA11funct=!{e},{Down 10},{Right},{Down 5},{Enter}
ButtonCA12funct=!{p},{Down 13},{Enter}
ButtonCA13funct=!{p},{Down 14},{Enter}
ButtonCA14funct=^{e},{Tab 13},{Enter}
ButtonCA15funct=ERROR
ButtonCA16funct=ERROR
ButtonCA17funct=ERROR
ButtonCA18funct=!{e},{Down 14},{Right},{Down 4},{Enter 2}
ButtonCA19funct=!{e},{Down 14},{Right},{Down 5},{Enter 2}
ButtonCA110funct=ERROR
ButtonCA111funct=ERROR
ButtonCA112funct=ERROR
ButtonCA113funct=ERROR
ButtonCA114funct=ERROR
[CustomActionButtons2]
ButtonCA21name=ERROR
ButtonCA22name=ERROR
ButtonCA23name=ERROR
ButtonCA24name=ERROR
ButtonCA25name=ERROR
ButtonCA26name=ERROR
ButtonCA27name=ERROR
ButtonCA28name=ERROR
ButtonCA29name=ERROR
ButtonCA210name=ERROR
ButtonCA211name=ERROR
ButtonCA212name=ERROR
ButtonCA213name=ERROR
ButtonCA214name=ERROR
ButtonCA21funct=ERROR
ButtonCA22funct=ERROR
ButtonCA23funct=ERROR
ButtonCA24funct=ERROR
ButtonCA25funct=ERROR
ButtonCA26funct=ERROR
ButtonCA27funct=ERROR
ButtonCA28funct=ERROR
ButtonCA29funct=ERROR
ButtonCA210funct=ERROR
ButtonCA211funct=ERROR
ButtonCA212funct=ERROR
ButtonCA213funct=ERROR
ButtonCA214funct=ERROR
[CustomActionButtons3]
ButtonCA31name=ERROR
ButtonCA32name=ERROR
ButtonCA33name=ERROR
ButtonCA34name=ERROR
ButtonCA35name=ERROR
ButtonCA36name=ERROR
ButtonCA37name=ERROR
ButtonCA38name=ERROR
ButtonCA39name=ERROR
ButtonCA310name=ERROR
ButtonCA311name=ERROR
ButtonCA312name=ERROR
ButtonCA313name=ERROR
ButtonCA314name=ERROR
ButtonCA31funct=ERROR
ButtonCA32funct=ERROR
ButtonCA33funct=ERROR
ButtonCA34funct=ERROR
ButtonCA35funct=ERROR
ButtonCA36funct=ERROR
ButtonCA37funct=ERROR
ButtonCA38funct=ERROR
ButtonCA39funct=ERROR
ButtonCA310funct=ERROR
ButtonCA311funct=ERROR
ButtonCA312funct=ERROR
ButtonCA313funct=ERROR
ButtonCA314funct=ERROR
[CustomActionButtons4]
ButtonCA41name=ERROR
ButtonCA42name=ERROR
ButtonCA43name=ERROR
ButtonCA44name=ERROR
ButtonCA45name=ERROR
ButtonCA46name=ERROR
ButtonCA47name=ERROR
ButtonCA48name=ERROR
ButtonCA49name=ERROR
ButtonCA410name=ERROR
ButtonCA411name=ERROR
ButtonCA412name=ERROR
ButtonCA413name=ERROR
ButtonCA414name=ERROR
ButtonCA41funct=ERROR
ButtonCA42funct=ERROR
ButtonCA43funct=ERROR
ButtonCA44funct=ERROR
ButtonCA45funct=ERROR
ButtonCA46funct=ERROR
ButtonCA47funct=ERROR
ButtonCA48funct=ERROR
ButtonCA49funct=ERROR
ButtonCA410funct=ERROR
ButtonCA411funct=ERROR
ButtonCA412funct=ERROR
ButtonCA413funct=ERROR
ButtonCA414funct=

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