@taenovella Are you using the direct link when uploading? If you don't, it won't work.

@Olepsis I tried but it still did not work ><

Also, keep in mind that you can only use images from Imgur, Photobucket, Imageshack, and Tumblr.

As for putting a cover image, the option "Set cover image" is your answer. It should show up on the information box of your story. (Where subscribers, upvotes, etc. are shown.)

"If you have imgur account you can upload the pics and there's a "direct link" you copy-paste it"
-my lovely friend jojojoana who helped me when I had that exact same issue! I hope this helps you too n,n