I tried to update from 1.1.3 to 1.0.2 and recieved this error report
Mods loaded: 24
ModLoader 1.2.5
mod_4096Fix v4 for 1.2.5
mod_BE MC: 1.2.3 ; BE: 1.2.3
mod_CodeChickenCore 0.5.2
mod_MinecraftForge 3.1.3.105
mod_ModLoaderMp 1.2.5v1
mod_NotEnoughItems 1.2.2
mod_JammyFurniture 3.2
mod_IC2AdvancedMachines v4.0
mod_AdditionalBuildcraftObjects 0.9.1-97 (MC 1.2.5, BC 3.1.5)
mod_BuildCraftCore 3.1.5
mod_BuildCraftBuilders 3.1.5
mod_BuildCraftEnergy 3.1.5
mod_BuildCraftFactory 3.1.5
mod_BuildCraftTransport 3.1.5
mod_BuildCraftSilicon 3.1.5
mod_AdditionalPipes 3.1.0 (Minecraft 1.2.5, Buildcraft 3.1.5, Forge 3.1.3.103)
mod_Clevercraft V1 - 1.2.5
mod_ItemDescriptions V1 - 1.2.5
mod_EE 1.4.4.0
mod_EnderStorage 1.1.1
mod_BuildCraftZFP (Forestry Package)
mod_Forestry 1.4.4.4
mod_HiddenDoors 1.1.0
Minecraft has crashed!
----------------------
Minecraft has stopped running because it encountered a problem.
--- BEGIN ERROR REPORT 8ec3b3bd --------
Generated 5/9/12 2:31 PM
Minecraft: Minecraft 1.2.5
OS: Windows 7 (amd64) version 6.1
Java: 1.7.0_04, Oracle Corporation
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
LWJGL: 2.8.3
OpenGL: ATI Radeon HD 5500 Series version 4.1.10524 Compatibility Profile Context, ATI Technologies Inc.
java.lang.VerifyError: (class: mod_IC2ThermoBlock, method: HandleGUI signature: (I)Lug;) Incompatible argument to function
at java.lang.Class.getDeclaredFields0(Native Method)
at java.lang.Class.privateGetDeclaredFields(Unknown Source)
at java.lang.Class.getDeclaredFields(Unknown Source)
at ModLoader.setupProperties(ModLoader.java:1763)
at ModLoader.addMod(ModLoader.java:293)
at ModLoader.readFromModFolder(ModLoader.java:1276)
at ModLoader.init(ModLoader.java:887)
at ModLoader.addAllRenderers(ModLoader.java:189)
at ahu.<init>(RenderManager.java:86)
at ahu.<clinit>(RenderManager.java:14)
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 20304062 ----------
]
I'm also using MultiMC to run several instances of Minecraft 1.25
thanks