This is working for me: /customer/sfc/servlet.shepherd/version/renditionDownload?rendition=THUMB720BY480&versionId=068E2000004WCBqIAO&operationContext=COMMUNITY&contentId=undefined&page=0

This is working for me: /customer/sfc/servlet.shepherd/version/renditionDownload?rendition=THUMB720BY480&versionId={versionId}&operationContext=COMMUNITY&contentId={contentId}&page=0