i think its a yes captain browny sunset really wants the powers so she stole the element of harmony from twilight and if she has it she will invade the whole equestria which is bad.
What i like in season 1 is episode 8 (look before u sleep) they were like arguements with apple jack and rarity in twilight's first slumber party, meanwhile in season 2 is episode 9 (sweet and elite) when rarity is hard on making the clothes for the fashion show by her friends
almost all ponies in the seasons 1 until 3 are in that movie and the most of them are photo finish,apple bloom,sweetie belle,scootaloo,twilight sparkle(main character), pinkie pie, big mac, fluttershy, rainbow dash,... etc
i am really exited about this! i was just tired on the old ones but i dont know what will happen after twilight become a alicorn or having a crush on flash this is getting nerviousxited!!!