RE: Getting an overview of reinforcements
Excellent breakout on the reinf lines. For your columns D and E, for the units, the values are bit flags to indicate various statuses. No idea of what they all are, but they are the same as for on map units. I think, for example, they can indicate travel mode.
Column M is for number of units in that reinf group.
J may be fatigue for the unit, but I am guessing from long ago memory.
For combined units, you can have additional columns for the units that are combined in the on map unit.
Hope that helps.