AFAIK Automatically tracks should give a notification of a new post in a topic. I don’t understand why searching would make a difference. I will have a look.
Yes, that’s the one causing the tracking - I have changed the default to 10 minutes - but if you have already changed it that should still stick - best to check.
Yes, that’s pretty much how it works. I’m in maling list mode right now (for testing), however once we go live I will turn that off since I plan to use the forum as a forum. The good thing about discourse is how many options you have control the level of notifications etc. I suspect most people will tweak it to their needs over the first few weeks.
I’m not sure about the 10 minutes. I think I dropped it to 5 when I was looking at new topics where you would typically spend a much shorter time looking at them when there were not many posts.