The link does not seem to be valid.

This may also mean that no updates were released since your Loopsynth was built, and therefore no binary compatible with your unit was generated on the server for downloading.

You can check if you have the latest firmware by keying in #4112 (as explained here) and comparing that number to the most recent firmware (usually mentioned in the latest post on the main page, or in the most recent manual).

For example, as of January 2023, the latest firmware is 1.0.118 (released January 2022) and is indicated like this: