IIRC if units are flanked they shoot at the new threat but do not change their facing. Infantry runs out of ammo already after 20min. Artillery shoots into elevated ground when the enemy is behind the elevation and doesn't care.

Artillery is firing into their own troops and doesn't care. In Tactical battles, the soldiers look gorgeous, but gameplay is rather stupid. The Campaign mode looks good, but the AI behaves irrational, shuffles around tiny units from A to B and from B to A without any other meaning than to slow down the AI's turn. I must admit I haven't tested any NTW mods yet to see if there is an improvement. I played RTW and MTW2 before (IMHO RTW was the best of these and the engine is best suited for that era). Recently I gave Napoleon Total War another go, but I got bored again after about 3h.