ok so I just want to make sure I understand this correctly:

I declare a 1 unit for an attack and my opponent declares one unit for the defense.

step 1: the winner of the edge battle strikes first. his unit kills my unit (I now have no units ready in the

engagement area)

Step2: action window

step 3: the loser strikes with one of his units (if able) I can now focus Chewy (with his crossbow) to strike against the objective and the defending unit.

step 4: action window

step 5: check play area for ready units and continue to alternate strikes until all units are exhausted

Basically I can focus Chewy to strike during step 3 even if I no longer have a unit ready in the engagement. It is only after step 4 that I, or my opponent, has to have a unit ready in the engagement to focus Chewy to strike.

Is that correct?

Should work, according to what I understand of the timing during engagements, but you might get clarification from FFG if that's not good enough for you

ok so I just want to make sure I understand this correctly:

I declare a 1 unit for an attack and my opponent declares one unit for the defense.

step 1: the winner of the edge battle strikes first. his unit kills my unit (I now have no units ready in the

engagement area)

Step2: action window

step 3: the loser strikes with one of his units (if able) I can now focus Chewy (with his crossbow) to strike against the objective and the defending unit.

step 4: action window

step 5: check play area for ready units and continue to alternate strikes until all units are exhausted

Basically I can focus Chewy to strike during step 3 even if I no longer have a unit ready in the engagement. It is only after step 4 that I, or my opponent, has to have a unit ready in the engagement to focus Chewy to strike.

Is that correct?

That is correct, as has been confirmed by Nate (posted elsewhere, but quoted earlier in this thread).