The first time i've runned the game it went smoothly but the second time i've runned the game "Lionheart Has Stopped Working" Error Message, Please help me cuz I wanna play this game.

Can you tell us if you changed anything software wise between the first and second time you ran the game? Have you updated all of your drivers? Have you tried running the game as an admin?
Can you post a DXDIag for us to have better look at what may be ailing you?

If I run the trainer, it causes this error when I try to play the game. Are you running the trainer?