Hi Bertrand,

Thanks for the catch. You can evade this problem (for M108, anyway)
by downloading

http://www.projectpluto.com/coe.dat

to your Guide directory, replacing the copy that may already be there.

The problem is that the files had names such as "ursa-maj.txt". In
transferral to an ISO-9660 CD, they got renamed to "ursa_maj.txt". The
above file provides the correct file names.

NGC 4636 and 4889 appear to be victims of cross-referencing disagreements.
The former is "a.k.a." 4624 in the PGC, which leads to "4624 and 4664"
from the SAC 7.2 database. The latter is a.k.a. 4884. I'll have to do
a bit of digging through the latest NGC-IC (the best source of answers
I've found for such questions) in an effort to unsnarl that mess.

-- Bill