@Moosmann - which ascom driver are you using? I have been using Per Frejvall's ascom driver and I have had a half-dozen or so auto-meridian flips and everything works well with the settings Gunny outlined:
Also tick the box 'Wait for Meridian' option in SGP.
After my first auto-meridian flip with my GM1000HPS (I have only had the mount 3 months or so) I tried using the 10 Micron ascom driver and I too had an error message generated by SGP and a subsequent re-set of the Minutes to Meridian Flip from -5 to 0 by SGP. I never tried the flip and quickly reverted to Per's driver.
Not sure if you have posted on the 10 Micron Forum but I know ChrisLX200 a UK imager has the GM2000HPS and automates his sessions with SGP - perhaps he will share his settings.
HTH
Barry