When two chart apps place primary stars differently, check birth date conversion, location, time zone, and hour first. Then compare the Zi Wei anchor and primary star layout. Only after inputs match should the calculation method be investigated.
When two chart apps place the main stars differently, compare calendar setting, birthplace, time zone, and birth hour first. Then locate the earliest difference in Life Palace, Five Phase Bureau, and the Zi Wei anchor. A transformation table disagreement is a different problem from a main star placement disagreement.
Compare birth conversion and hour, then Life Palace, bureau, Zi Wei anchor, and all primary stars. Pause interpretation until the first placement difference is explained.