Having a similar issue. The game crashes back to launcher quite frequently with the message
EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x000000007399c4a8, pid=736, tid=3860
#
# JRE version: Java(TM) SE Runtime Environment (7.0_51-b13) (build 1.7.0_51-b13)
# Java VM: Java HotSpot(TM) 64-Bit...