I think the story is a bit better than in Save the Spirit. Of course I also used cheats, including the save-anywhere one.
Never release a level without playing through it! Any playtesting would've shown that the level is unmanageable due to no save points.
Playing the level all over again also isn't fun, there should be an option to go back to the point where you are about to find the orb.
The way the orb is hidden is bad too. You can rely on player exploring that screen a little bit, but finding that specific non-solid square makes no sense. Good old detector could be put in one of dead ends of the tunnels to be then used here.
The good ending includes many empty screens of ghostly path.
Minor bugs include climbable invisible wall to the right of the beginning, voids if you jump off the cliff before going into catacombs, numerous critters walking on air...