They are from the revenge ending (Ceris 2/3), NTR Ending (Impreg. scene) and 2 from the main game. I finished all endings, they are still greyed out.
Also I went through the ending on the saves provided with the game and tried there. Same thing. The NPC does not work and the scenes are not viewable.
That really is a weird one. 10,11,13,14,15 you say? I did a bit of digging, and found that 11 (waterfall scene) didn't use the correct trigger to unlock it in the reminiscence room, and used an unrelated one in a Thania side quest. Still, I added the same incorrect trigger with the spirit, so it should have unlocked it anyway had you talked to it. Same with 10 and 13. Those 2 scenes are mandatory, and you should have watched them and activated their trigger no matter what, otherwise you couldn't have progressed the story. Since you say you did watch them, we can assume the trigger was turned off somehow afterwards, but I double checked with the search function of the engine, and there are no mention of the triggers except: in the scene, with the spirit, and in their respective reminiscence room (3 places where they should be) and nowhere else. To be honest, all of this baffles me.
The spirit cannot unlock 13,14, and 15, since those are ending related, but if you've done the respective ending, they should have unlocked no matter what.
The only reason I could think of is:
1) There is an issue with your file. Are you using the windows version provided in the OP?
2) There might be a misunderstanding somewhere. For example, the only way you can access 13 and 14 is if you use the room from your harem in the revenge ending. Did you do that and still nothing?