Error in running Commandos

Hi
I am having difficulty in playing my favorite games Commandos : Behind enemy lines and Commandos : Beyond call of duty.
I purchased those games from steam and installed them. The game installed pretty well and was running till the intro. When the intro ended the screen went black and all i can hear is theme sound in the background. Since the first installation, the game ran completely for once (I dont know how Neutral ). Every time i open it the intro plays and the screen goes black with same theme sound in background. This is happening for both my games. I really need help. Kindly help me.
Thank You

What are the names of the main .exe files of those games? Then I can add them to the blacklist of the codecs.

This will only help for issues with playback of the videos in the games. Any issues with the game itself are not caused by the codecs.