We just added a bunch of new keyboard shortcuts in our editor:

P                         Toggle Pedal
Home                      Go beginning of part
End                       Go end of part
Ctrl/Cmd + G              Prompt & Go to a measure number
Ctrl/Cmd + Left           Go previous measure
Ctrl/Cmd + Right          Go next measure
Ctrl/Cmd + Shift + Up     Go previous staff
Ctrl/Cmd + Shift + Down   Go next staff
Alt + ?                   Display shortcuts
Shift + Alt + Left        Shorten current duration
Shift + Alt + Right       Lengthen current duration

We have also added a new version of the keyboard shortcuts cheatsheet on our Help Website. To view them while using the editor, you can click on the "?" icon on the top right of your screen and choose "Keyboard Shortcuts", or simply press "Alt + ?".