New pullets in hiding - should I be worried?

I bought 3 10wk old australorp pullets last Saturday. They seem happy and healthy - eating, drinking, pooping, pooping, pooping.

I Put them in the new coop I built: https://www.backyardchickens.com/a/coop-casa-vista-a-la-piscina last Sunday after having them inside overnight just to watch that they're healthy. Sunday evening they came downstairs for a while, and I threw them some vegetable scraps which they didn't seem interested in. That was the last time I've seen them downstairs. It's now Wednesday.

So, a few questions:

1. Should I be concerned that they're not venturing downstairs yet or am I being too ambitious? Is it all just too scary for them? How long does it take for them to realize that this is home and get comfortable?
2. Is it too young for them to be interested in veggie scraps? When I had them inside, they were scratching and pecking the newspaper. If they're too young, when can I expect them to start?
3. I intend to free range them whenever I can be home to supervise, but my dad recommended keeping them locked for a few weeks until they get that the coop is home. I've clipped their wings...when should I start letting them out?
4. Should I just drag the suckers out into the daylight and make them go downstairs and/or into the yard? How can I encourage them out?

Sorry for so many questions. One thing to note is that there are two dogs next door that bark, so this might be freaking them out a bit, but they came from a farm environment where I would have thought that kind of noise would be normal.

Any advice, suggestions gratefully accepted!

LD

 

Thanks for the response. I know, I'm an anxious first time mom.