Do you just want that LED to change color every second? If so, you can use the LED gadget and tie it to one of the Data Simulator tags, like the Square Wave A…
If you need to do something more elaborate, you could use an Image Indicator w/one image for one value (like “on”) and another image for another value (like “off”).
Have you seen our handy svg library? I generated these two SVG files using the last symbol in that last set of categories. Note the link to the video at the top of the page that shows how to do use the tool:
I hope that helps!