In your first screenshot, the code you put down make it so that attack 1 should never trigger since :
On attack 0, you set the boolean "Attacking" to true
When attack 0 is done, you change the comboAttackState back to 0
So in your attack 1 conditions, you can never have comboAttackState to 1 AND not being Attacking.
Moreover in the timer "comboStart" you do not set "Attacking" back to false either.
And same for Attack 2.
From what I read from this code, conditions cannot logically be true and then trigger at some point.
I'm afraid I'm not sure what exactly you are willing to achieve.
It could be easier if you could provide a small c3p that focuses on your combo and describe exactly, step by step what you want the obj_player to be doing, how the human player can interact and what are the consequences you want from those interactions.
Then it will be easier to clearly establish a "screenplay" of what is to happen and "translate" it to the event system.