after trying my own images with that I’m not seeing thumb versions created. Before i start creating thumbs myself and uploading them am I missing something?
It won’t make the thumbnails for you-- it’s just an example of how to add them. Thumbnails are rarely necessary, however. They’re certainly not necessary simply for having images appear smaller, just if you have very large ones. If you do have a lot of large images and you’re not using the CDN, for example, to help with load time, you can upload your own thumbnails and reference them.