try using spofs after you allocate a sprite. spofs 0, 24, 43 where 0 is the management number, 24 the x coordinate and 43 the y coordinate to move the sprite to the desired location.
how would I do this for a 4 piece sprite (and how would i "spawn" a 4 piece sprite, as if I placed the Boss Skeleton in the upper left corner of the SP screen)
For sprites larger than 16x16 use Phillips suggestion. If you want a character composed of several sprites like say a hero and the weapon they hold then use splink sprites. I have attached an splink sprite example for your amusement. You can of course use both together
Attached is a splink demo. Use Phillips suggestion when you want something bigger than 16x16, and link sp to make a character out of several pieces, or both ideas at once.