I wonder, how about calling them directly and asking why they haven't fixed them for so long? Maybe that way things start to move.. maybe those email/log reports aren't even reaching devs? I don't know any G Data dev whom to pm personally and tell directly, but that might be needed. I have experienced that approach usually helps with other security software vendors.
I just asked for a refund on 5\10 device license of Total Security. Too much trouble to get problems fixed.