So, DIrect guide and the reversal of the Y axis is one very confusing issue, or it can be. If you have a mount that tracks fairly well, like an ME II, this baked in error can confuse the heck out of you. I"ve got it sorted now. I want to share
what I learned to save the next guy some time. When using Direct guide, calibrate in the usual way, east, DEC zero. Once you've done that prove to yourself your guiding is good by guiding on that same star you used to calibrate. Note that over ten minutes your guiding is solid. Don't worry about aiming west. Now, fire up ACP and run some plan. Watch the error in EITHER X or Y, but NOT both climb. You MIGHT see the star rapidly drift off if your mount is not well polar aligned, BUT, you may also see what I saw, that the error in EITHER X or Y climbed initially slowly, and in fact, with seeing tossed into the mix, the error might even appear to drop for a bit, but generally its climbing. THAT was what confused me. I saw what LOOKED like routine back and forth in the autoguider error but what I was REALLY seeing was error stacking with seeing tossed on top....making it LOOK like I was autoguiding. When I studied this over an hour with multiple runs the pattern became obvious. This is NOT obvious initially IF your mount tracks well to begin with, because the initial errors are so small that they can be obscured by seeing. Over time however, the error pattern ( generally rising error in ONE axis) always comes through. That I proved to myself thoroughly. Once you've seen this repeatable pattern, go back into ACP preferences, under guiding, and turn on "reversal of Y axis". Why is this confusing, well its also the case that the "Y" axis, due to PA might be the "X" axis. I noted the stacking error in EITHER axis but NEVER both axis. So, once you turn on the reversal, the problem vanishes. After I got this sorted out last night I captured many hours of pictures, all autogiuded, correctly. This is confusing to watch and sort, sorry if my explanation assumes you knew something you don't feel free to ask questions. But, if your autoguiding suddenly isn't right this is probably the culprit. I'm back in business in a serious way, amen.
Peter