Thanks muraria - all finished now. Never heard of this particular 'fabulous beast' before! I had a wrong letter in one of the entries crossing the Alpine peak, so no wonder I got stuck there.
Agree with other posters - the puzzle is a work of art in its construction, but there do seem to be too many unnecessary clashes. That said, I liked it and found it enjoyable - certainly difficult, but not so difficult as to make me give up on it entirely.