Hi Bernd,
It just occurred to me that there's another way to get Guide to
recognize Machholz (1994r). That would be to download the file
http://www.projectpluto.com/machholz.txt
Then run Guide and click on Extras... Add MPC Comets/Asteroids,
and click on the line at the bottom. This will bring up a file-selector
dialog; select 'machholz.txt'.
'Machholz.txt' contains the same elements Guide already uses,
except that I've added in some probably not-very-accurate magnitude
data. Guide will use these new elements instead of the old ones,
and 1994r will start to behave "normally".
-- Bill