MotoCMS 3 Media Library used Adobe Creative SDK software for editing images of Media Library. However, some time ago Adobe discontinued support of the Creative SDK Image Editor UI. You can learn more about this event here.
Image editor was working some time since the official end of support of the Creative SDK Image Editor UI by Adobe, but unfortunately, their servers do not accept connections right now and we're afraid they won't get back.
However, we'd like to assure you that our developers are working on an alternative solution and one of the future updates of MotoCMS 3 Control Panel will probably include another image editor.
You can check release notes here - we'll definitely list the updated image editor in this list once it appears!