sorry but what is steam version;i try to tell you my hl2; first i create a folder then i extract the rar files from dvd to this folder;in the read me text it says that copy the launcher.exe as a shortcut to your desktop then click it and play the game; before my this system i run the game again in this way but i wasn't using xp x64; now my oc is xp x64;can i tell you,idon't now, is this a steam version.By the way you can go a episode whatever u want by choosing it in the game (if it works 
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