I see you've already received interpretations for many of these expressions. When I come across an expression I don't understand in a book, I google the word or phrase and often find the meaning that way.Sometimes I might google the word and England or the word and Australia, etc. If I'm reading a particularly difficult book, I sometimes read it while sitting near my computer.

From my first trip to the UK: Conductor on the overnight train from London to Edinburgh asked if he should Knock Us Up in the morning. Knowing it couldn't mean what it means in the US, I looked at my English friend and asked her what she thought. She said yes. When we were alone she explained it meant "wake us up" and looked shocked then laughed when I explained that in the US it meant "get pregnant."

My friend's mother was doing laundry and asked if my Flannel Wanted Boiling. I knew that Wanted meant "needed" but the other words confused me. She was wondering if she should literally boil my washcloth to clean it. (I said, "Only if you are doing everyone else's.)