Here is the log starting at the error.
2013-04-15 10:04:29 [iNFO] [sTDERR] java.lang.RuntimeException: java.lang.NoClassDefFoundError: cpw/mods/fml/common/asm/ASMTransformer
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.setupHome(FMLRelauncher.java:192)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.relaunchApplet(FMLRelauncher.java:259)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.appletEntry(FMLRelauncher.java:229)
2013-04-15 10:04:29 [iNFO] [sTDERR] at net.minecraft.client.MinecraftApplet.init(MinecraftApplet.java:25)
2013-04-15 10:04:29 [iNFO] [sTDERR] at net.minecraft.Launcher.init(Launcher.java:127)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.spoutcraft.launcher.GameLauncher.runGame(GameLauncher.java:210)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.spoutcraft.launcher.GameUpdater.runGame(GameUpdater.java:136)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.spoutcraft.launcher.skin.components.LoginFrame.onEvent(LoginFrame.java:309)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.spoutcraft.launcher.skin.components.LoginWorker.doInBackground(LoginWorker.java:103)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.jdesktop.swingworker.SwingWorker$1.call(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.util.concurrent.FutureTask.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at org.jdesktop.swingworker.SwingWorker.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.Thread.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] Caused by: java.lang.NoClassDefFoundError: cpw/mods/fml/common/asm/ASMTransformer
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.defineClass1(Native Method)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.defineClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.security.SecureClassLoader.defineClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.net.URLClassLoader.defineClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.net.URLClassLoader.access$100(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.net.URLClassLoader$1.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.net.URLClassLoader$1.run(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.security.AccessController.doPrivileged(Native Method)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.net.URLClassLoader.findClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:134)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.registerTransformer(RelaunchClassLoader.java:96)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchLibraryManager.handleLaunch(RelaunchLibraryManager.java:271)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.setupHome(FMLRelauncher.java:172)
2013-04-15 10:04:29 [iNFO] [sTDERR] ... 15 more
2013-04-15 10:04:29 [iNFO] [sTDERR] Caused by: java.lang.ClassNotFoundException: cpw.mods.fml.common.asm.ASMTransformer
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:211)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] ... 30 more
2013-04-15 10:04:29 [iNFO] [sTDERR] Caused by: java.lang.NoClassDefFoundError: net/minecraftforge/event/Event
2013-04-15 10:04:29 [iNFO] [sTDERR] at net.minecraftforge.transformers.EventTransformer.buildEvents(EventTransformer.java:59)
2013-04-15 10:04:29 [iNFO] [sTDERR] at net.minecraftforge.transformers.EventTransformer.transform(EventTransformer.java:35)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.runTransformers(RelaunchClassLoader.java:292)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:199)
2013-04-15 10:04:29 [iNFO] [sTDERR] ... 32 more
2013-04-15 10:04:29 [iNFO] [sTDERR] Caused by: java.lang.ClassNotFoundException: net.minecraftforge.event.Event
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:211)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2013-04-15 10:04:29 [iNFO] [sTDERR] ... 36 more
2013-04-15 10:04:29 [iNFO] [sTDERR] Caused by: java.lang.AbstractMethodError
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.runTransformers(RelaunchClassLoader.java:292)
2013-04-15 10:04:29 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:199)
2013-04-15 10:04:29 [iNFO] [sTDERR] ... 38 more
2013-04-15 10:04:35 [iNFO] [sTDOUT] Exiting mod pack
I read the EAQ, etc the error isn't there.