As stated in our app listing, Crush.pics can automatically compress product, collection, and asset folder images. This means that images stored in the Settings > Files area of Shopify cannot be automatically compressed and this is a limitation of Shopify, not our app.
In the past, we've recommended manually compressing these images using free tools such as TinyPNG, which you still can do, or now you can compress them manually in the app using the same process.
Note: This will not auto-update the image on your site. You will need to upload it to the app, download it, and upload it to Shopify.
1. On the Crush.pics dashboard, click the Manual Upload bar under All Images
2. Select Balanced(Lossy), Conservative(Lossless), Custom compression
3. Drop images onto the uploader or click Add Image to select images from your computer
4. Your images will load onto the list underneath - Wait for compression to finish
5. Click the down arrow next to Details and click Download
6. Right click on the image and click Save Image As...
7. Upload the image to Shopify wherever you want to use it