I am disappointed that you didn't provide more details than "it does not work". This is the equivalent of telling your doctor "it hurts".
did integrity check on steam
F1 at main menu ACTIVATED
started game where there is a FIGHT and can see the units and the gems
clicked on a unit to open it's cards to see it's stats
press Numpad 1 to Capture Units ACTIVATED
clicked away from unit, then clicked back to see it's card again
press Numpad 2,3,4
clicked away from unit, then clicked back to see it's card and the numbers have changed
trainer tested working 100%
15 minutes wasted.
I have no idea if you can try to play against other human players, but likely the trainer wont work against real human opponents.
What OS are you on? Where did you buy the game? Any way to provide your game .exe and a savegame so we can check it?