How to get 5.1 audio with Cyberlink Audio Decoder?

I Love Cyberlink audio decoder. Im watching all movies with it. But i cant get 5.1 out of it, only stereo. If i open properties on Cyberlink Audio Decoder it only allows me shoose stereo or dolby surround. (whats the diference?) But its not 5.1 audio. I have tried to connect AC3 filter with Cyberlink Audio Decoder with Graphedit but they do not agree connection. Can someone please help me? Maby im using an older version, where to get newer?