That's what's puzzling me Larry.   Usually I go to the main download page:

http://www.minorplanetcenter.net/iau/MPCORB.html  and  do a full nightly download of the full asteroid database with MPCORB.DAT.gz  This is my working file for the observatory computer.

I used to download the critical list asteroids from this webpage as well, but CR objects are no longer broken out.

On the same webpage is the Comets file, which produces the CometEls.txt  I've copied this to Guide 9 back in Oct 2015 but haven't updated it since.  Perhaps this is the source of my getting 45P in 3 different locations.

Now, there's also a Comets/Soft02Cmt.txt file running around on the MPC website.  It is in a completely different format than the CometEls.txt file.  Bill didn't say which file Guide 9 pulls down from Extras.  And he didn't say which file is used for comets.

I'm used to working with asteroids winding up in Guide's MPCORB.dat file.  Doc Clay's MPEC Sort routine somehow updates the MPCORB.dat file for just critical list asteroids.  And since it does comets as well, I'll bet he's got the critical comets in there too.  Running MPEC Sort replaces the MPCORB.dat and neatod.dat files in Guide 9.  So now I've added neatod.dat to the mix?

Does anyone know for sure 1) which file does Guide 9 use?  2) The difference between CometEls.txt and Soft02Cmt.txt?

Puzzled Pete