After I thought that I've lost the release-version of the X-Mas 1992 Demo (only had fragments left) forever, I finally found it on an old disk. The demo was not very special but as there was an article about the Party in wiki, and also the demo was not spread very much, I updated the wiki-article and uploaded the demo.
Thanks man!
Here's the link: Xmas 1992 Party - CPCWiki (http://cpcwiki.eu/index.php/Xmas_1992_Party)
CRTC specific it would seem...
That awakes some nice memories, that was a great party... :) And it's always fun, that you had to read 5minutes scrolltexts until something happened :D