Hi John,

You can click on Extras... Edit Comet Data, select the object in
question, then click on Delete. Guide will toss out the elements
you've added and drop back to the elements that are "built into" it.

Regarding Find_Orb: (quick check) Looks as if you're right; I
shut off epochs before JD 2300000 = 31.5 January 1585 as being probably
erroneous (as you say, epochs for those dates would probably be of
theoretical interest only). However, you _can_ enter (for example)
an epoch of "25 12 1200" to specify an epoch of Christmas 1200.

-- Bill