i had a black screen with mineshafter on this i posted on their forum they replied: Check on the forge forums.
so heres the log.
[Mineshafter Squared] C:\Users\Jesse\AppData\Roaming\.mineshaftersquared/mineshaftersquared.properties
Current proxy version: 3.8.0
Gotten proxy version: 3.8.0
Trying to proxy on port 9010
Proxying successful
asdf
Request: GET http://mcupdate.tumblr.com/
No handler. Piping.
Piping finished, data size: 25522
Request: GET http://static.tumblr.com/qfn3sex/ezom7y7iq/bg_main.png
No handler. Piping.
Piping finished, data size: 434
Request: GET http://pixel.quantserve.com/pixel/p-19UtqE8ngoZbM.gif
No handler. Piping.
Piping finished, data size: 35
executePost: http://session.minecraft.net/game/getversion.jsp
Request: POST http://session.minecraft.net/game/getversion.jsp
GetVersion
To: http://mineshaftersquared.com/game/getversion/3.8.0
2012-08-26 14:59:39 [iNFO] [ForgeModLoader] Forge Mod Loader version 3.0.71.289 for Minecraft client:1.3.2, server:1.3.2 loading
2012-08-26 14:59:44 [iNFO] [sTDERR] Exception in thread "Thread-10" java.lang.RuntimeException: cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindClassException: java.lang.ClassNotFoundException: net.minecraft.Launcher
2012-08-26 14:59:44 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.relaunchApplet(FMLRelauncher.java:269)
2012-08-26 14:59:44 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.appletEntry(FMLRelauncher.java:212)
2012-08-26 14:59:44 [iNFO] [sTDERR] at net.minecraft.client.MinecraftApplet.init(MinecraftApplet.java:25)
2012-08-26 14:59:44 [iNFO] [sTDERR] at net.minecraft.Launcher.replace(Launcher.java:136)
2012-08-26 14:59:44 [iNFO] [sTDERR] at net.minecraft.Launcher$1.run(Launcher.java:79)
2012-08-26 14:59:44 [iNFO] [sTDERR] Caused by: cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindClassException: java.lang.ClassNotFoundException: net.minecraft.Launcher
2012-08-26 14:59:44 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.ReflectionHelper.getClass(ReflectionHelper.java:161)
2012-08-26 14:59:44 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.FMLRelauncher.relaunchApplet(FMLRelauncher.java:254)
2012-08-26 14:59:44 [iNFO] [sTDERR] ... 4 more
2012-08-26 14:59:44 [iNFO] [sTDERR] Caused by: java.lang.ClassNotFoundException: net.minecraft.Launcher
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.net.URLClassLoader$1.run(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.net.URLClassLoader$1.run(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.security.AccessController.doPrivileged(Native Method)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.net.URLClassLoader.findClass(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.lang.ClassLoader.loadClass(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.lang.Class.forName0(Native Method)
2012-08-26 14:59:44 [iNFO] [sTDERR] at java.lang.Class.forName(Unknown Source)
2012-08-26 14:59:44 [iNFO] [sTDERR] at cpw.mods.fml.relauncher.ReflectionHelper.getClass(ReflectionHelper.java:153)
2012-08-26 14:59:44 [iNFO] [sTDERR] ... 5 more
