@Meanlucario
The prequel trilogy wad adapted first becuase those were the most recent movie at the time of the games release (IIRC LEgo Star Wars came out about a few weeks before Revenge of The Sith released), so that’s what Lucasfilms wanted them to do so it could tie into the newest movie
As for the New Hope teaser being different then what the actual level would be, it as like that becuase they wanted to give a short teaser for what will be the next game that was stll in development, and they wanted to give the players the chance to have a level as the villains as a reward for finishing the game