I hear you on the spending half an hour to get a half hour nap - it's so frustrating. If it helps, those days are already a distant memory for me and it's only been 7 months.
Oh well, life with a newborn is not meant to be predictable!
I'm certain that newborns are sent to us to teach us to live in the moment and go with the flow!
Don't worry too much about the sleep window. I didn't have another LO to look after and I could never get her down at "exactly the right time". I think with newborns there is no right time. Some LOs just need a lot of help getting to sleep.