I downloaded MultiMC 3.1 for Windows and was unable to get the game to run at all. I dropped computer craft and just loaded forge (under the minecraft.jar tab) and then IC2 and MFFS (under the /mods tab). Game starts just fine but I am still unable to actually craft any blocks. I'm going to go get fresh copies of all the mods in case I got some bum-version.
have you tried using NEI just to make sure the recipes appear? or some mod that displays the recipes of certain items