Help installing optifine with Voltz

[zbryanz]

So my computer runs terrible with voltz (I have a terrible computer) so I wanted to install the optifine mod. When I install it with the vanilla minecraft it runs a lot better so anyways I downloaded the 1.4.6 version of optifine and I dragged and dropped it all into the minecraft file (I know it's the right one). When I log into voltz it freezes at this light blue screen. When I go to the log in screen and select the version I am using 1.0.11/1.4.7/Rec. Build . So I don't know if I am using the wrong version of optifine or something but please help.