Tried this with 3 different browsers
Chrome - Couldn't upload images at first. Loader dissapeared without errors. After mutiple refreshes and image size changes, I was able to upload images but couldn't drag them in the editor for positioning so got stuck there.
Firefox - Everything went well until the end where I got the "There was an error uploading your photos and generating your Game Face. Please try again." error and got stuck there.
Safari - Same as with Firefox.
Tried again with Firefox and inspected the network traffic. Saw that the back-end system gave an error that entity is too large so I decreased the image size and tried again. After that still got the error and back end responds with status 500 error which means that something is broken on their server side.
I get it that this is a complex functionality and has a lot of edge cases. But I know that a user friendly error handling is not that much work. If the image sizes are too large, then the error should indicate this. And having 500 server errors on live system for more than an hour indicates a really sh*tty development team.
Really disappointed in EA system. Lost my mood for playing UFC for good. Or any other EA game for that matter.