Am I right in thinking that the French do not get to activate one piece at the start of every turn, but rather only get to activate one piece at the start of the first turn, and therefore the French may not get to activate any pieces on the second and/or third turns? Do the French only get to activate units on the second and/or third turns if they are adjacent to an enemy-occupied locale or one of their start locals has been taken?
The French get to choose any one unit for activation on their first turn. This is FIRST TURN ONLY.
A French unit is automatically activated if there is an Austrian unit adjacent to it at the start of the French turn. This is whenever it happens; in some turns it may be that no French units are activated this way, in other turns, multiple units may be activated.
Should the Austrians ever occupy a French start-up locale (even if only temporarily), at the start of each French turn after that, the French can select any two units for activation. This is EVERY TURN.