To start the game, you just start the launcher, as you did, and press "play". From there the game starts as normal, as it did years before and you should end up in the main menu, where you can choose to use Single player, Multiplayer etc.. So from the looks of it, everything should be fine with your installation.
I have no experience with FH2 and Windows 8, but first of all, you maybe should try to run the .exe in compatibility mode and as an administrator. My second guess would be, if your screen goes black, but it didn't load the game, you may have a firewall, which askes you to allow connection (to the game spy replacement server). During that the loading of the game is put on halt.
If none of them above works, start the game in windowed mode, to see of any error messages appear.