Oxidative browning in must will go away when the yeast starts to consume the oxygen. Pectic enzyme will be needed, and enough sugar to reach the target alcohol level. EC-1118 is good yeast and widely available and works well without need of nutients. Concord type (Labrusca) grapes aren't the...
Wines are typically hazy due to pectin or protein, or depending on the base...starch (root wines). If you add Campden tables (SO2) at the same time as an enzyme it is likely your enzyme will not work, beacause sulphur kills enzymes. Headspace can be remedied by adding marbles until your carboy...