It did not occur to me at first to check all possibilities, but I did now. Without grip it works correctly, and it does with the grip if battery is in the left compartment, Canon can read them both, ML does only the left one, and if you have the battery in the right one - it reads the 100%, but color warning works. Somewhat I'm used to stick battery in the right side. Sorry, my bad...
Would it be possible to add the second battery indicator? or have a menu choice? There are quite many who use battery grips (especially with video and time lapses) and that would benefit us. thanks, anyway!