When you are about to go into a fight, stop. Back up the game in progress (simply make a copy of the Stevefire.mdb file) and then do the fight. Something goes wrong, replace the current Stevefire.mdb with the copy, and try again. Once you are confident you can do the fight, then you can stop following this procedure, but until then, this should help learn how things work (or don't).
I use dedicated Aegis class point defense destroyers for fleet operations, and once the settings are taken care of in the F8 screen, they work well. Ideally, the range of the AMM ASS needs to be long enough to let you engage at sufficient range to get multiple intercepts on the same salvo, which is also dependent on the speed of your AMM. For me, a sensor that spots them at 2m km is adequate, with an AMM speed in the 28,000 k/s to 35,000 k/s range. I also recommend the 3 AMM per missile PD setting, 4 tends to overkill too much, 2 tends to let missile leak through too much. I expect I'll swap to the 2/1 setting after I get my missile tech up high enough.