First of all I have to say that this is probably the most ambitious mission project I have seen so far. I've been playing since OFP times and never have I encountered a similar immersive singleplayer experience (except for saok's missions perhaps...)! The amount of work that was spent on this one must have been tremendous. However, whenever I engage the enemy for the first time during a mission, the game crashes. Trying to reload the last savegame again leads to a crash. If I go back to the penulitmate savegame and then engage the enemy, everything works fine and I can continue with the mission. Very strange, isn't it? Did anybody encounter the same problem? By the way it doesn't even matter if I'm spotted by the enemy, shoot them or bombard them with artillery. It seems like as soon as the AI is forced to react to my actions, the crash is triggered. I tried it both with ACE and several other mods activated and without any mods, no difference.