Why not? The next dead ball was the horn (or not). :)

The RPP only applies after a TO or intermission. Not after a dead ball.

Yes, indeed. ...The dead ball with the horn.

Some of this is semantics, since the rules don't explicitly state when the RPP starts and when it ends. You say it ends when the ball becomes live (I guess). It might also end when neither team is delaying. In any even,t even if it's not part of the RPP, but you're still going to have a T under 10-1-5b, right?

If a team tries to complete a throw-in but fails, then it's a violation. If they fail to even try, then it's a T. The RPP lessens the penalty for the T (to a V)under certain circumstances.

Once Team A violated and Team B got the throw in, and did so successfully, the RPP situation is over. If the horn blows for halftime a minute later, a violation afterward is a new situation - no T for the first violation. It's a new RPP situation. 10-1-5-b (except for the RPP carve out for TOs and Intermissions) refers to an actionless contest, which would be a T for the first violation and then can be a forfeit situation.