I'm travelling on a reward ticket, over multiple segments. I'm wondering how many times I will have to retrieve and re-check my bags.

The outbound is YOW-AC-YYZ (o/n) -AC-YVR-AC-KIX (o/n) -NH-HKG
I arrive YYZ at 2105 and depart the next morning at 0700
I arrive KIX at 1625 and depart the next morning at 1040

Can I check the bags all the way thru?

Specifically, since I'm only spending 10 hours in YYZ, will they be able to check the bags thru? How about the overnight and change of airlines at KIX?

On the return, it's 5 segments HKG-OZ-ICN-OZ-LAX-AC-YVR-AC-YYZ-AC-YOW

I know that I will have to pick-up in YVR for customs, but will they check it thru LAX?

Thanks for your help with this. It's a big trip and I'm trying to plan all the little details so it goes well. (and I couldn't find anything on search or on ac.com)