Not sure why this isn't working. I seem to have selected the layer that I want but the pathItems on that layer aren't being selected or changed.
var docRef = app.activeDocument;
var layerRef = docRef.layers;
for (i=0; i<docRef.layers.length; i++){
if (layerRef[i].name === "Perflines"){
var perfColor = new CMYKColor(100, 100, 0, 0);
layerRef[i].pathItems.selected = true;
layerRef[i].pathItems.strokeColor = perfColor;
layerRef[i].pathItems.strokeWidth = 1;
alert(layerRef[i].name);
}
}