Thanks for your clarification Bill. However, it leaves a problem. From
your reply, I take it that the LX200 actually sends RA/dec data to the
computer. So when I do a 'you are here' click on the alignment star,
how much of the data is retained? For example, I am finding on every
session that after alignment of the telescope on a known star, and then
telling Guide to add alignment star - even if I did it yesterday on the
same star - then future pointing accuracy is always a bit off in one or
both directions. This takes a long time to adjust. I first assumed
that it was using old data that I should delete.

Essentially, what is the process on a nightly basis: should I still
point the scope at the known star (as indicated by centralising it in
the CCD field), and then get Guide on the star - and how do I tell Guide
that it is on target?

TIA

Lawrence