OK, I think this is the deal so far.....
1) Humans learn (steal) the secret of creating life (AI, ie Cylons) from the "Lords of Kobal" while on Kobal
2) 13th tribe (all Cylons) leave for Earth, 12 tribes leave for the Colonies. Why??
3) 13th Tribe settles on "Earth", learns or becomes able to reproduce, and resurrection tech falls into disuse..and is forgotten
4) The "Final 5" are Earth cylons that re-discover resurrection tech, anticipating bad things.....
5) Earth gets nuked (by newly created Centurions made by the skinjob 13th tribe?), and the Final 5 resurrect in a ship in orbit
6) Final 5 leave (no FTL) to warn the 12 tribes of humanity of the dangers of not treating any AI constructs well......
7) Final 5 arrive at the colonies 2000 years later and too late, during the 1st Cylon War (Colonial-created Cylons are trying to make their own skinjobs...can only make hybrids)
Final 5 convince the Centurions to stop the war, in exchange for creating skinjobs & resurrection ability
9) Final 5 create the skinjobs (models 1-8)
10) Model#1 (Cavil, or John) corrupts and destroys the Daniel line, and captures the Final 5
11) Cavil resurrects the Final 5 with altered memories, then dumps them on the Colonies. Other models are altered to not know of the 5.
12) Events of the Miniseries.....