happy.melon.wiki wrote:

Checked on test.wiki; the issue is the non-ASCII character in the *name*; using the character in the script file is ok, it seems. And adding a non-ASCII character to the name of another script that had strictly ASCII scriptfile, also made it disappear. Retitling for clarity.

Gadget IDs have to follow the rules for XML IDs, so they are restricted to alphanumeric ASCII characters and can't start with a number. This is by design, and also documented on the extension's description page http://www.mediawiki.org/wiki/Extension:Gadgets.

It would in theory be possible to use the same encoding MediaWiki uses for section IDs to get around that limitation. It would need some fiddeling. If you feel a real need for this, reopen as a feature request.

Closing as invalid, since this is expected behavior.