Put the summary of the bug you're having here
What I expected to happen was...:
My resource pack/textures to change.
What actually happened was...:
My game exited.
Steps to Reproduce:
1. Load up minecraft.
2. Play a level, go to options.
3. Change to a custom resource pack and try to continue gameplay.
Environment
OS: Windows 7 (ver 6.1, arch amd64)
Java: 1.7.0_21 (by Oracle Corporation)
Launcher: 0.9.2 (Dev) (bootstrap 2)
Minecraft: 13w24b (updated Fri Jun 14 14:54:59 BST 2013)
Based on a crash report provided in this issue, I believe with high certainty that this report may be a duplicate of MC-17831. You can view all information known about this specific crash at MCX-679.