Why isn't sin() function working in KSP?

I have not been able to get ANY of the advanced functions (sin, cosine, power, exponents, sqrt etc) and I have no idea why. Went with a different approach and settled on linear equations. At velocities below 32, the "eccentricity" of the randomness added to the velocity linearly decreases, and same thing for 96 and up. This makes writing for low dynamics more realistic, and makes writing for high dynamics more predictable.

I don't know if posting this is even allowed, but this is actually an edited version of the Humanize script that comes with Kontakt. The only problem is the stock script is flawed. If more than one note is played at the same time, the velocity randomness is applied to all notes equally. This means that if you have different dynamics in each hand of a marimba for example, they will all be stuck to one dynamic. That's fixed with this.

The other functions are omitted (pan, volume, tune) since they're not useful for percussion stationary acoustic percussion.

I'm not a programmer by any means so use at your own risk.

on init
   set_script_title("Humanize Timing & Velocity")

   declare ui_knob $Timing (0,100,1)
   set_knob_unit ($Timing, $KNOB_UNIT_PERCENT)
   set_text ($Timing,"Note On")
   $Timing := 0
   make_persistent ($Timing)
   move_control ($Timing,3,2)
   declare $new_event

   declare ui_knob $e (0,100,1) {velocity eccentricity}
   set_knob_unit ($e, $KNOB_UNIT_PERCENT)
   set_text ($e,"V Eccen.")
   $e := 0
   make_persistent ($e)
   move_control ($e,4,2)
   declare $v
   declare $m {-minimum, maximum}
end on

on note
   ignore_event($EVENT_ID)
   wait(random(0, $Timing * 1000))
   $new_event := play_note($EVENT_NOTE, $EVENT_VELOCITY, 0, -1)

   $v := $EVENT_VELOCITY
   $m := 127
   if($v <= 32)
      $m := 127 / 31 * $v - 127 / 31
   end if
   if($v >= 96)
      $m := 127 / -31 * $v + 127 * 127 / 31
   end if
   change_velo($new_event, $v + random(-$m, $m) * $e / 200)
end on

Thanks for your response, EvilDragon. I did try this and still getting the "expression expected" error.