Slitherine

Hello
2 Days ago i have installed the free game and test it, all seems work fine, so i buy the US marine campaign. The problem is now the game start, i play some turn but than the game freeze and no way to exit, i have to turn OFF the iMac.
any help is graitfull
thanks Fabio

Problem solved: if i sue the 2D maps all works fine with the 3D crash