Feekkee, did you copy all optifine files and perform a "replace all" in the modpack.jar folder? When I attempted this, the "FML is setting up minecraft environment" loading screen got stuck at the "Minecraft validated, launching..." step and wouldn't proceed further. I also tried removing the META-INF folder after it hanging the 1st couple of attempts, but that didn't resolve the issue either.
Here's the crash report from my last attempt...depending on which optifine I tried some of the details changed between reports but the errors / issues on the reports were the same:
---- Minecraft Crash Report ----
// There are four lights!
Time: 5/24/13 7:16 PM
Description: Failed to start game
org.lwjgl.opengl.OpenGLException: Invalid value (1281)
at org.lwjgl.opengl.Util.checkGLError(Util.java:59)
at org.lwjgl.opengl.DrawableGL.checkGLError(DrawableGL.java:82)
at org.lwjgl.opengl.Display.swapBuffers(Display.java:617)
at net.minecraft.client.Minecraft.func_71357_I(Minecraft.java:517)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:406)
at net.minecraft.client.MinecraftAppletImpl.func_71384_a(SourceFile:56)
at net.minecraft.client.Minecraft.run(Minecraft.java:732)
at java.lang.Thread.run(Thread.java:680)
A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------
-- System Details --
Details:
Minecraft Version: 1.5.1
Operating System: Mac OS X (x86_64) version 10.6.8
Java Version: 1.6.0_45, Apple Inc.
Java VM Version: Java HotSpot 64-Bit Server VM (mixed mode), Apple Inc.
Memory: 32339688 bytes (30 MB) / 117288960 bytes (111 MB) up to 1606287360 bytes (1531 MB)
JVM Flags: 1 total; -Xmx1536m
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Suspicious classes: FML and Forge are installed
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML:
LWJGL: 2.9.0
OpenGL: NVIDIA GeForce 8600M GT OpenGL Engine GL version 2.1 NVIDIA-1.6.36, NVIDIA Corporation
Is Modded: Definitely; Client brand changed to 'fml,forge'
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
META-INF concerns for all the previous posts: the Meta-INF file does exist in the default modpack.jar from technic. Best to just leave it. I tried it with & without in the above attempts, neither worked.