Full circle...bad news, good news
Bad news - I am unable to get SGP to connect to the ST-i as the imaging camera.
Good news - I really don't want the ST-i/guidescope combination to be what APPM uses for modelling ... Duhhhh
I can connect the st-i as guide camera and run PEMPRO
I can connect my 6D as imaging camera in SGPro (which is what i should have done all along ...Duhhh)
SGPro is happy
APPM is happy
Clouds are happy ...Oh well.
Anyway, I have a configuration that I understand now after much farting around...duhhhh
Given clear skies, I know I can refine the PEC and develop a good model in APPM, leading to unguided imaging.