Great mod, allows for a lot more characters beyond the main ones with unique moves and works very well. It feels fresh not playing as Mario, Luigi, Wario, Waluigi and Toad only.
My only minor issues are that the "Let's-a go" voice when entering levels seems to now play from the world's center 0,0 coordinates, instead of everywhere for the player (which I think is how it was like a few updates prior); this makes the sound very quiet (and on some levels like Cool, Cool Mountain, completely mute), and that the game does not apply any reverb effects onto voice lines, meaning they are much clearer and sharper than the voices of the default characters, a bit inconsistent. I've also noticed that with a lot of characters (but not all), it plays the dreaming sound right away once the character lies down while sleeping, and they don't continue snoring afterwards.
