Not a real bug, but perhaps this could be implemented smoother with a little system support...
GM can only be bought without coppers - but autoplay treasures brings all coppers in play. Perhaps it is intended that players have to think about this in advance - but nevertheless it can be undone (which at the end is a little bit cumbersome).
Solution could be a separate button for the buy phase of GM games ("autoplay without coppers") - a little bit like it was in MF (keeping in mind, that this service was mandantory due to the missing undo button).