whats the difference between spades slick and jack and where does all the felt stuff (green buildings) take place in relation to everything else? are snowman and the black queen two different people?

Spades Slick is the Jack Noir from Karkat’s session, he just changed his name. The Intermission inside the green Felt manor takes place on Alternia long after the events of Sgrub. Snowman is the Black Queen from Karkat’s session so yes, they’re the same person.