Skins wont make your fps better if anything they'll make them worse. Fps models, Nope never heard of that. Who gave you this information ?.

Just lower all the video settings.

Well i dont play cs, Never have never will. That file from clownbase may work on that game, But a simlar file for this game doesn't exist as far as i know. Like fragger said, Lower your gfx settings you'll have to settle with the game looking like crap, But you fps will rise a bit.

Hmmm could you also be having an issue with your rate setting ?