This Isn't working for me...Help?

I did a brand new install of the Windows 7 64 bit OEM.
I installed the version 3 Divx Tech Preview and some MKV play with no sound while others wont play at all...am I missing an extra codec or something?

Thus ,making the consumer to

Thus ,making the consumer to have an ease at its consumption and also in saving a lot of productive time. Ultimately, making the person dependent on it for his own benefits. This is unlike to the times of traditional cooking where people had to spare time and even do physical labor compared to the modern technically advanced time of today.-FXDD

My problem's not with Divx

So I downloaded a sample file and it played nice. So I'm guessing I have a makeMKV problem.

Me either

I thought I downloaded all necessary files, but MKV's will simply not play on WMC on the Xbox. I can play the mvk's through WMPC but that's about where it stops. Can anyone link me to a series of steps that I should be taking?

You also need an AC3 Filter

You also need an AC3 Filter for Mkv's with AC3 sound

No Video

WMP wouldn't open my mkv, installed AC3 Filter and it opens now, but only sound - no video. Just shows a musical note.

Any ideas?