only 2 reasons i can think of. There not released yet, usually there released on a specific turn. There usually dim when they haven't been released and the icon is bright when you can use move them. The other reason might be the setting in options to click to control allied troops. hope it helps.
I'm getting chewed up as the Russians in the Rakitnoe scenario, most of my AT assets are just about gone, i think i love to counterattack to much. I had a victory on turn 3, now i'm on the low side of a draw after turn 5 and things aren't looking up. So for turn 6 my repair unit and some more reserves get released and so i'm deciding what to do and it's late so i decide to make my moves tomorrow, my dumba** hits the clock icon instead of the back arrow....oooops nobody gets to move. i really needed that repair unit to get to work and to use those reserves to switch out some battered units.....I think I'm fu**ed
Love the ebb and flow of this game.
Enjoy when you can, and endure when you must. ~Johann Wolfgang von Goethe
"Be Yourself; Everyone else is already taken" ~Oscar Wilde
*I'm in the Wargamer middle ground*
I don't buy all the wargames I want, I just buy more than I need.