Black Apron

It's not really on the fine focus... you have to take out the whole gear reducer and attach the EAF knob to the focuser main shaft... so the EAF will be acting attached to the "coarse" adjustment.

Thank you for this... I just installed mine and it works perfectly...

I think your problem might not have to do with PHD itself directly... it happens to me from time to time that vibrations from the filter wheel turning (especially if the destination filter is several slots away), is strong enough to make PHD loose its lock. If you have a long FL scope, any small vibration will impact the star and if on top of that the focus changes, then you might end up having this kind of problem.... I've been looking for a way to have SGP automatically stop guiding for a couple of seconds before moving the filter wheel and resume after a few seconds to allow for settling (or after autofocus), but I haven't found a way...