setLoop.jsx

//Snippet for adding a time remap loop for each selected layer
//CC-BY, Nik Ska, 2013

var setLoop = this;

setLoop.loopExpression = "try{\n\n\tshift=effect('ADBE Effect Parade')('ADBE Slider Control')*thisComp.frameDuration;\n\t(time+shift)%thisLayer.source.duration;\n}\ncatch(err){value}";

setLoop.go = function(){
	var activeComp = app.project.activeItem;
	if(activeComp && activeComp instanceof CompItem){
		var sel = activeComp.selectedLayers;
		if(sel){
			for(var s = 0; s < sel.length; s++){
				if(sel[s].canSetTimeRemapEnabled){
					sel[s].timeRemapEnabled = true;
					setLoop.setSlider(sel[s], 'Loop Shift', 0, '');
					sel[s].property("ADBE Time Remapping").expression = setLoop.loopExpression;
				}
			}
		}
	}
}

setLoop.setSlider = function(masterLayer, slName, slValue, slExpression){
  //adding a slider to the master layer
  var sl = masterLayer.property("ADBE Effect Parade").addProperty("ADBE Slider Control");
  sl.name = slName;
  sl.property("ADBE Slider Control-0001").setValue(slValue);
  sl.property("ADBE Slider Control-0001").expression = slExpression;
}



setLoop.go()