From: Bratislava, Slovakia
IIRC Flak count is number of barrels/4, so F2 would mean 8 barrels
For the Guns be warned, these can be mortars, infantry guns, howitzers, anti-tank guns, dual purpose guns, coastal defense guns, etc. It is best to compare the actual TOE.
For the Infantry: 48 - I presume thats 4 squads (indicated by AV4) of 12 men each (I think squad sized Machine Guns could be counted here too like .50 cal M2HB squad, or .30 M1917 Browning MG)
Other troops: 2188 - should be Support squads, engineer squads, Naval Support squads, etc
The Mouse Over is really just for the rough information, and do not tell about particular effectiveness of the unit (8x80mm Mortars counts the same as 8x57mm ATG and 8x155 Howitzers)