I managed to get the 20400-3 version working in 3.0.2 with a couple minor changes to the MetaHud.lua file (\Interface\AddOns\MetaHud\MetaHud.lua):
Replace all instances of "PLAYER_COMBO_POINTS" with "UNIT_COMBO_POINTS"
Line 2055 is currently:
points = GetComboPoints()
change it to
points = GetComboPoints("pl...