I've been trying to get help on the Feed the Beast forums for these issues but they don't seem to know. So anyway my issue is of the access violation variety. Here is the log when it crashes. If you need anything else i'll get it.
So... When does it crash? When you load the launcher, the modpack, a world? Please be more specific.
It will crash while i'm playing and then won't let me relaunch it after before crashing. It gets onto the mojang screen and before the title page it crashes.
http://pastebin.com/ZVyhA7Jc
It will crash while i'm playing and then won't let me relaunch it after before crashing. It gets onto the mojang screen and before the title page it crashes.