I was playing the 5th scenario(Bullet is not molded).
I was pulling back from the main objective when one of my regiments got stuck in a creek(as seen on attached picture). 17 th Connecticut.
They where frozen and did not fire back(still had ammo). The score was rocket diving down to -18512 this was happening in less then a minute!!
When they eventually routed the score didnt drop anymore and my entire corps had -18018 in score and I quit.
I know now I should have a save game but I'll try to reproduce the bug again.
My specs:
Vista 64 bit
6 GB Ram
Geforce GTX 260