Register the game after purchase on Steam

[BuZzEvilly]

I bought the game on Steam and now I want to register it on the Matrix website. Where can I get the serial number? The FAQ on Steam says what to look for on the mail in the check. But he's not there. How to be and what to do?

Thanks!

P.S.
By the way, the same problem I had with the purchase of WITE.
But the Scourge of War: Waterloo all went well! (the number was in a separate tab on the Steam).

[CapnDarwin]

If it still works (Steam to Matrix is a hit or miss based on game and time frame), go into Steam, Right click on the Red Storm entry and go down to the second selection "View CD Key". Write down the CD key. Try that key over at Matrix Games to register the game there. Again, it may not work in that direction anymore due to changes and incompatibilities between Steam and MAtrix systems. Keep us posted if it works for you.