*FACEPALM* you
it can not download argo-2.25.jar guava-12.0.1.jar asm-all-4.0.jar
download manually argo-2.25.jar guava-12.0.1.jar asm-all-4.0.jar and put them in your lib folder
yes
MCPatcher edit base class
yes i know optifine edit base class to but it is compatible with Forge
http://www.minecraftforum.net/topic/249637-142-optifine-hd-a7-fps-boost-hd-textures-aa-af-and-much-more/
If you have a ModLoader mod that does not work with FML/Forge,
*TELL US*, and we will fix it immediately. We *NEED* the ForgeModLoader-client-0.log, so post it in the Support & Bug Reports