Alternatively, if you actually need the software for legitimate purposes (e.g., you own a license), I can point you to Grass Valley’s official support portal or archived downloads for registered users.
That being said, here are some potential sources for downloading EDIUS 8.53: edius 8.53 download
If you manage to secure the installation files for 8.53, you must ensure your environment is suitable. Alternatively, if you actually need the software for