I had nearly the same issues as this: <a href="https://app.roll20.net/forum/post/5345929/forbidden-error-while-accessing-s3-object-storage-for-map#newtopic" rel="nofollow">https://app.roll20.net/forum/post/5345929/forbidden-error-while-accessing-s3-object-storage-for-map#newtopic</a> For me, certain images were succeeding at upload, but mysteriously having retrieval forbidden from S3. After too long I finally noticed that the failed images were JPEGs. Then I checked and, yep- the upload page says "JPG, PNG, GIF" So obviously this is a case of "user error" since I didn't know how to use the interface... but for the sake of future users who don't know how to use it- can you please make the instructions here more clear? Perhaps: "Acceptable formats are JPG, PNG, and GIF only." I'm loving the product so far, but little things like this are bit of a headache. Thanks for listening to this feedback!