What’s the link to your website?
You’re not using those image links on your own website, right?
The reason I ask is because all of those images are External links from their demo site. None of those images are from the actual Theme itself, they are just external links to images. They don’t have anything to do with the theme or the theme’s performance.
Also, you’re not really supposed to use those image links on your own site, those are just for demo purposes, you’re supposed to upload any images you plan to use on your own site/server. The speed in which those images are delivered will be based partly on the theme, WP, and how good your hosting/server is. If you have a slow server, then the images will show up slow (not much any theme can do to override that).
So what you’ll need to do is use images that are uploaded to your server so that your site isn’t relying on another external server to display your images.
Keep in mind: If they remove or change some of the images on their demo, then those image links won’t work on your site. That’s why it’s recommended that you upload images that you want to use on your own server, and then use those links for your images. This is how it works for any theme or website you use.
Hope this helps 🙂
.
