1.You are not looking for "Auto 1 attack target", but for "Auto 1 isnotattacking attack target".
I can tell you right now, that this is NOT possible.
You can only change packet for attack in client(by dll)and server(?) side, but with this elfbot should be useless, bot without targeting? Uhuhu..
Why this is not possible?
Because you cannot check when elfbot attack and when player attack, on target in client you send packet to select target, elfbot doing same action.
Ym... You can only write target limiter, but normal player can target with 8-12ms duration, when elfbot targeting with "auto 1"
Something like 40-60ms(tested).
2. I don't know much about combo leader (not tested).
Sorry for Engilsh xd