I have the same problem, .710 patched from previous version, I have been CTD'ing randomly on occasional battles on any terrain, the game NEVER CTD'ed on me before.
It does seem to happen when I'm in the process of clicking with the mouse, attacking an enemy, but I'm not sure I can relate to that since I'm most often pressing the mouse button attacking enemies, anyway, it never happened while I was passive yet.
Extremely annoying.