Waiting for your shot at the sequence.....only listing events up to 12.30pm.
I'll give it a shot....
My best chronology (utilizing the items previously mentioned)....
Shelley sighting of Oswald on the first floor.
Piper sighting on the first floor.
Oswald returning to the 6th floor after noticing Jarman and Norman (the "alibi").
[DVP Interjection -- I don't think the "noticing Jarman and Norman" part happened at all. Hence, I need to place Oswald "returning to the 6th floor" BEFORE the "elevator race". But it is POSSIBLE that Oswald, for some reason, returned to the first floor AFTER the elevator race. And if that was the case, then another "Oswald Returns To The Sixth Floor" entry would be needed below, denoted with ********.]The "Elevator Race" - Oswald on 5th floor (most likely, possibly 6th).
Givens sighting of Oswald during the cigarette trip.
Williams arriving on the fifth [sic] floor for lunch.
[You surely meant to say SIXTH floor here, right? Since Williams didn't eat his lunch on the FIFTH floor that day.]Jarman and Norman leave front of TSBD to go up.
Jarman and Norman arrive at the 5th floor windows.
Williams departing the 6th floor and joining Norman and Jarman on the 5th floor.
[*******]Rowland sighting with man holding rifle (12.15pm).
Belknap having seizure.
[Not sure what this event has to do with this particular topic, however.] ~shrug~Ambulance arriving in DP.
[Like Belknap, I can't see how this event is very meaningful to this discussion.]Oswald taking position in the SN prior to shooting.
[It's possible Oswald did this twice, though.]Brennan sighting someone in the SN.
Euins sees someone (with a "pipe") in the 6th-floor SN window.
Oswald leaving the 6th floor.
Oswald entering the lunchroom for his coke.
Dougherty going to the 5th floor.
[Dougherty's testimony is a total mess. A timeline of his actions and movements cannot be determined with any degree of accuracy, IMO.]Dougherty taking the elevator to the first floor after the shots.
[See last comment.]