First forgive me, i'm doing as much reading as I can atm. I use a steam account with several games that i've purchased, inc. Garry's Mod 10, CS:S, HL2M, HL2:LC and TF2 . I want to get DoD:S, Portal, HL2, HL2:Ep1 and HL2:Ep2 working with Gmod, since I already own the Orange Box on both XBox360 and PS3 I don't want to re-purchase the games on PC just for use with Gmod. With the free DoD:S weekend a few weeks back I started the download of the game but didn't finish (although I did recieve the GCF), also I have a downloaded version of Half-Life 2 and Portal on disc (which works but not with Gmod - because they are cracked versions). After a bit of reading I found a thread which tells me what GCF's I need for what games and believe I correctly listed the ones I need; Sound Source.gcf Source Models.gcf Source Materials.gcf Source Engine.gcf Base Source Engine 2.gcf Source 2007 Shared Sounds.gcf Source 2007 Shared Models.gcf Source 2007 Shared Materials.gcf Source Binaries.gcf Episode 1 Shared.gcf Half-Life 2 Game Dialogue.gcf Half-Life 2 Content.gcf Day of Defeat Source.gcf Half-Life 2 Episode One.gcf Half-Life 2 Episode Two.gcf Portal Content.gcf Portal English.gcf The only ones I don't currently have in the list are Episode 1 Shared.gcf, Half-Life 2 Episode One.gcf and Half-Life 2 Episode Two.gcf. While it's easy enough to get the GCF's, i'm wondering because I already have the required Half-Life 2 [exc. Ep1 and Ep2], Portal and DoD:S files and they are in my C:\Program Files\Valve\Steam\SteamApps folder why Gmod won't let me use in-game? The best reason I can think of is because I haven't run Half-Life 2, Portal or DoD:S through Steam, even though they are installed and work. Can anyone help me out with what I need to do. I don't honestly know if cracked game+legit gmod works or only cracked game+cracked gmod work together. If it can, how do I make it work?