IC2 and addons..

Okay, so I used MVC to downgrade my Minecraft to 1.2.5 to run IC2 v1.95b and Rocket Science v0.89. I installed MC Forge 3.1.2.90 and Modloader. I also tried to install Computercraft 1.41. I got this:

--- BEGIN ERROR REPORT 76bd9724 --------
Generated 1/24/13 7:51 PM

Minecraft: Minecraft 1.2.5
OS: Windows 8 (amd64) version 6.2
Java: 1.7.0_11, Oracle Corporation
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
LWJGL: 2.4.2
OpenGL: Intel(R) HD Graphics version 3.1.0 - Build 9.17.10.2828, Intel

java.lang.NoSuchMethodError: ach.setTileEntityRenderer(Ljava/lang/Class;Laar;)V
at dan200.computer.client.ComputerCraftClient.load(ComputerCraftClient.java:35)
at mod_ComputerCraft.load(mod_ComputerCraft.java:80)
at ModLoader.init(ModLoader.java:891)
at ModLoader.addAllRenderers(ModLoader.java:189)
at ahu.<init>(ahu.java:77)
at ahu.<clinit>(ahu.java:8)
at net.minecraft.client.Minecraft.a(Minecraft.java:394)
at net.minecraft.client.Minecraft.run(Minecraft.java:732)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT 34e6d70a ----------

So can anyone tell me any better versions to use or if I'm doing this wrong?

This is the full script:

Mods loaded: 6
ModLoader 1.2.5
mod_MinecraftForge 3.1.2.90
mod_ComputerCraft 1.41
mod_CCTurtle 1.41
mod_IC2 v1.95
mod_ZZZMissile 0.89

Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem.

--- BEGIN ERROR REPORT 76bd9724 --------
Generated 1/24/13 8:32 PM

Minecraft: Minecraft 1.2.5
OS: Windows 8 (amd64) version 6.2
Java: 1.7.0_11, Oracle Corporation
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
LWJGL: 2.4.2
OpenGL: Intel(R) HD Graphics version 3.1.0 - Build 9.17.10.2828, Intel

java.lang.NoSuchMethodError: ach.setTileEntityRenderer(Ljava/lang/Class;Laar;)V
at dan200.computer.client.ComputerCraftClient.load(ComputerCraftClient.java:35)
at mod_ComputerCraft.load(mod_ComputerCraft.java:80)
at ModLoader.init(ModLoader.java:891)
at ModLoader.addAllRenderers(ModLoader.java:189)
at ahu.<init>(ahu.java:77)
at ahu.<clinit>(ahu.java:8)
at net.minecraft.client.Minecraft.a(Minecraft.java:394)
at net.minecraft.client.Minecraft.run(Minecraft.java:732)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT cf7dab28 ----------

I don't remember, is there a certain way to install them?

I had rocket science and IC2 working, but when I installed ComputerCraft, it started giving me this message

Ok, so I figured out what is wrong. I reinstalled everything, in the order you guys gave me: modloader, mc forge, then the plugins: ic2, then rocketscience. However when I downloaded Computercraft, it was in zip format ( which was the main cause). However, changing the folder to a jar file still does not work. Is there anywhere I can download the jar file?

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