last version, hope it works ;)

var colors = [
2,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,3,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,
7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,
7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,
7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,
7,7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,
7,7,7,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,3,3,3,3,3,3,3,3,7,7,7,7,
7,7,7,7,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,7,7,
7,7,7,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,7,
7,7,7,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,7,7,
3,7,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,7,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,7,
3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,7,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,7,7,
3,3,3,3,3,7,7,7,7,7,3,3,3,3,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,7,7,7,3,3,3,3,7,7,
3,3,3,3,3,3,7,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,7,7,3,3,3,3,7,7,
3,3,3,3,3,7,3,3,7,7,7,7,7,7,3,7,7,7,7,7,7,7,7,3,3,7,3,7,3,3,7,7,7,7,3,3,3,3,7,7,
3,3,7,3,3,7,7,7,7,7,3,3,7,3,3,7,7,7,6,6,7,7,3,3,7,7,3,3,3,3,7,7,7,7,7,3,3,3,7,7,
3,3,3,3,3,7,7,7,7,3,7,7,7,7,7,7,7,7,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,7,7,7,
3,7,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,7,7,7,
3,6,6,7,3,7,7,7,7,7,7,7,7,7,7,7,7,7,6,6,6,7,7,7,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,
7,7,6,7,3,7,7,7,7,6,6,6,6,7,7,7,7,7,6,6,6,7,7,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,
3,7,7,7,7,7,7,7,7,6,6,6,6,7,7,7,7,7,6,6,6,7,7,7,7,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,
3,7,7,7,7,7,7,7,6,6,6,6,7,7,7,7,7,7,6,6,6,7,7,7,7,7,7,6,6,7,7,7,7,7,7,7,6,7,3,3,
3,7,7,7,7,7,7,7,7,6,6,7,7,7,7,7,7,7,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,
3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,
3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,3,3,7,7,7,7,3,3,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,3,7,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,
3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,7,7,7,7,7,7,3,3,3,3,3,3,
3,3,3,3,3,3,3,7,7,7,7,7,3,3,3,3,3,3,7,7,7,7,7,7,7,3,7,7,7,7,7,7,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,7,7,7,7,7,7,3,3,7,7,6,6,6,6,6,7,3,3,3,7,7,7,7,7,7,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,6,7,7,3,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,3,3,7,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,6,6,6,6,7,7,7,7,7,3,3,7,7,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,6,6,6,7,6,7,7,7,7,3,3,7,7,7,7,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,6,6,7,7,6,6,7,7,3,3,3,7,7,7,7,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,7,7,7,3,3,3,7,7,7,7,7,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,7,7,7,3,3,3,3,3,7,7,7,3,3,3,3,3,7,7,7,7,7,3,3,3,3,3,3,3,3,3,
3,3,3,3,3,3,3,3,3,3,6,7,7,7,3,3,3,3,3,3,3,3,3,3,3,7,7,7,7,7,7,3,3,3,3,3,3,3,3,3,

];
var colorsABGR = [];

//x/y is the lower left (or maybe 1 pixel below? fuck knows, check with drawTestImage() if you got it right)
var image = {
  x: 240,
  y: 775,
  width: 40,
  height: 50
};

var perfect_timeout = 60;

//update timeout for poor reddit servers (ms)
var get_delay = 500;

//always check the next pixel or increasingly skip more each loop?
//might help performance if many people run it
var use_skipping = false;
var skipping_max = 20;


// hooks
var client;
var canvasse;
var jQuery;

//will start here the first time
var currentDrawPosition = 2;

var currentLoop = 0;

r.placeModule("image", function(e){
  client = e("client");
  canvasse = e("canvasse");
  jQuery = e("jQuery");

  for(var i=0; i<client.palette.length; i++){
    colorsABGR[i] = client.getPaletteColorABGR(i);
  }

  startup();

});


function startup()
{
  console.log("skipping to first wrong pixel");
  var toWait = client.getCooldownTimeRemaining();
  for(var i = currentDrawPosition; i < image.width*image.height; i++){
    if(colors[i] === -1){
      continue;
    }
    var targetPoint = getPoint(i);
    var pixelColor = getPixel(targetPoint.x, targetPoint.y);
    if(pixelColor !== colorsABGR[colors[i]]){
        currentDrawPosition = i;
        console.log("starting at " + currentDrawPosition);
        break;
    }
  }
  setTimeout(attempt, toWait + Math.round(Math.random() * 1500));

}



function attempt(){
  console.log("tried to draw");
  var toWait = client.getCooldownTimeRemaining();
  if(toWait === 0)
  {
    tryDrawPixel();
  }
  else
  {
    setTimeout(attempt, toWait + Math.round(Math.random() * 1500));
    console.log("set a timeout");
  }
}

function tryDrawPixel()
{
  var toWait = client.getCooldownTimeRemaining();
  if(toWait === 0 && currentLoop < image.width*image.height)
  {
    currentLoop++;
    console.log("checking pixel " + currentDrawPosition);
    var targetPoint = getPoint(currentDrawPosition);

    $.get( "/api/place/pixel.json", { x:targetPoint.x, y:targetPoint.y }, function( data )
    {
      setTimeout(function() {
        //wait an extra half second for reddits servers


        console.log("x" + targetPoint.x + " y"+ targetPoint.y);
        if (data.color == undefined)
          data.color = 0;
        canvasse.drawTileAt(data.x, data.y, colorsABGR[data.color]);
        if (colors[currentDrawPosition] != data.color && colors[currentDrawPosition] !== -1)
        {
          client.setColor(colors[currentDrawPosition]);
          client.drawTile(targetPoint.x, targetPoint.y);
          console.log("drew pixel at " + targetPoint.x + "/" + targetPoint.y);
          var toWait = client.getCooldownTimeRemaining();
          setTimeout(attempt, toWait + Math.round(Math.random() * 1500));
          currentLoop = 0;
          console.log("set a timeout");
        }
        else
        {
          var positionIncrease = 1;
          if (use_skipping == true)
          {
            positionIncrease = Math.floor(Math.random() * (Math.min(0.2*currentLoop, skipping_max))) + 1;
          }
          currentDrawPosition += positionIncrease;
          if (currentDrawPosition >= image.width*image.height)
            currentDrawPosition = 0;
          tryDrawPixel(currentDrawPosition);
        }
      }, get_delay);
    });
  }
  else
  {
    var added_timeout = 0;
    if (currentLoop == image.width*image.height)
      added_timeout = perfect_timeout*1000;
    setTimeout(attempt, toWait + Math.round(Math.random() * 1500) + added_timeout);
    currentLoop = 0;
    console.log("set a timeout");
  }

}

function drawTestImage(){
  for(var i=0; i < image.width*image.height; i++){
    if(colors[i] === -1){
      continue;
    }
    var targetPoint = getPoint(i);
    canvasse.drawTileAt(targetPoint.x, targetPoint.y, colorsABGR[colors[i]]);
  }
}

function getPoint(i){
  var x = i % image.width;
  return {
    x: image.x + x,
    y: image.y + (i - x) / image.width - image.height
  };
}

function getPixel(x, y){
  return canvasse.writeBuffer[canvasse.getIndexFromCoords(x, y)];
}