The Brandfolder CDN will also pick whatever the first attachment is as the image, so if you re-order/edit the attachments it also updates the image all across the web.
Contact Support@brandfolder.com to manually expire the cache if you need it to expire faster, which usually takes about 10-15 minutes for it to change across the world.
How to Embed An Asset
1. Open the desired asset
2. Select Embed
3. Copy the code and insert on your website
4. To change the file type, simply replace the .png or .svg, etc. in the URL