A fun little game, surprised by the amount of maps there were!
For improvements:
-You could work a little on the volumes of certain sound effects, for example the portal sound was very loud and high pitched compared to everything else.
-You could experiment a little with the ghosts spawning only when you enter the room as currently you could snipe them from across the map and they wouldn't react (you can see the ghost and magic on the map so it's a matter of lining it up).
-Add some kind of filter or effect when rewinding time. The sound effect is alright, however, something to show which things are being affected, like a highlight on the objects that it's currently rewinding.
-Keeping the R button pressed is pretty overpowered since you can keep the ghosts in place forever. Perhaps adding special time enemies that are not affected by time or there's only a X amount of time ghosts can be rewinded.
Nice job on the game jam, seems you got quite a bit done in a week!