It seems that i cant pass vars or object expressions values into an action with x y parameters. I confirmed it by adding my own action into the edittime/runtime file. It only accepts number values only exactly. Is this a problem with the canvas plugin or Construct 2 itself? This is the code i placed, to add the clearRect function.
Edittime
AddAnyTypeParam("x", "the x position on canvas", "0");
AddAnyTypeParam("y", "the y position on canvas", "0");
AddAnyTypeParam("width", "the width from x", "0");
AddAnyTypeParam("height", "the height from y", "0");
AddAction(31, 0, "Erase canvas", "Canvas", "Erase at mouse x/y on canvas", "Erase at mouse x/y on canvas", "eraseWithColor");
Runtime
acts.eraseWithColor = function (x, y, width, height)
{
var ctx=this.ctx;
ctx.globalCompositeOperation = 'copy';
ctx.fillStyle = "rgba(0,0,0,0)";
ctx.clearRect(x,y,width,height);
this.runtime.redraw = true;
this.update_tex = true;
}