SetKeyDelay, 50	  

:*:1::
send, ^{F9}
loop, 8 {
send, +{left}
}
send, gra
send, {down}
send, {return}
send, {down}
send, s
send, {esc}
return


:*:2::
send, ^{F9}
loop, 8 {
send, +{left}
}
send, gra
send, {down}
send, {return}
send, {down}
send, s
send, {esc}
send, j
send, {esc}
return

; How it works: On selecting a note then pressing number "1" (or number "2"), the script presses a
; quick succession of standard keyboard shortcuts in Musescore which performs
; the following actions in the following order:
; Place cursor in palette search field,
; Select any text already typed into palette search field (by typing "shift+left arrow 8 times),
; Type "gra" to overwrite selected text (if any) and bring up the "grace note" palette,
; Press "down arrow" to select 1st option in palette (add grace note),
; Press "return" to add grace note to selected note,
; Press "down arrow" to transpose the grace note down a semitone,
; Press "s" to add slur,
; Press "esc" to deselect slur
; Stop the process.

;Option "2" is the same as "1" but re-spells the grace note (eg changes B flat to B natural)...