Here's a suggestion so you can make all keys be accessible from a pc keyboard in the piano roll instead of the 2 octaves it currently has.
2 top Row of letters for black and white keys.
WE UIO Black Keys e
SDF HJKL White Keys (easy way to remember, A and G computer keys are skipped)

(playing the 4th octave by default)

Z-M, and 1-7, and 1-7 numpad – hold down for different octaves 1-7 to be played on the black and white keys
These could be used as modifier keys or toggle switches.

simulate 3 pedals: hold down Alt keys, or Spacebar while pressing other black and white piano keys WEUIO or SDFHJKL

reference: piano layout, picture of octaves

Hope this helps.