Thanks a lot jgodfrey! Dynamic typing was the "problem".
Changing
var ppm_player = CPixelPerfectMovement.new(TICK_AMOUNT, Vector2(0,0))
to
var ppm_player:CPixelPerfectMovement = CPixelPerfectMovement.new(TICK_AMOUNT, Vector2(0,0))
did the trick. Now autocompletion works like a charm.
Perfect! Greetings Stefan