I ended up contacting the seller company and they told me to go to a local Dahon dealer store to get these issues repaired possibly under warranty. The seller mentioned they might cover the cost of the replacement/repair work. I think this applies both to bent chainwheel and to scratches. I got the same response from ThorUSA. They all directed me to a local Dahon dealer store.I got to the store today and they told me to leave the bike there. They are going to contact Dahon and ask for any replacement parts and if warranty covers any service. If it's not covered by warranty, the seller (as promised) might reimburse all costs.
Note, none of them told me to return the bike. I believe that damage is not critical and nobody wants to mess with the pain of returning it etc. So I left the bike at a dealer store and will wait for around a week or so to get any updates from them.
I also need to mention that the box was intact and not damaged at all. Bike inside didn't have any foam or support at all, it was just sitting there with pieces of bubble wrap around some areas of the frame. I don't know if it's normal. But it really looks like reseller just shipped me already damaged/scratched bike without any QC. I hope they repair my bike and I will be able to ride it finally in a week or two.
Here are few images of damaged areas that might not be clear enough on that video:
And I think I see the reason why they could advise me to go to the store instead, not to return it. Dahon online shop states this:
It looks like it's my case.
Well lesson learned, Dahon. I keep my fingers crossed that they repair it and make it rideable for years to come. But in future, I'm getting BF or Brompton.