Channeling stone : vous rappelez vous où elle se trouve ? ( Bachman Street)
Et surtout, savez-vous où je dois l´utiliser ?
1000 mercis.

C´est bon. J´ai trouvé.

Channeling Stone:

Where its found: Found on the counter of the Convenience Store on the Northeast corner of Bachman and Finney street

When to use it:
on the roof of the " Other School"
outside of the hospital before the moth boss
outside the motel
on the boat
on top of the lighthouse

You will know it worked when you see lights in the sky and Harry will say: That Light!? If used in all the right places the Alien ending will be unlocked.

Note: Must get the good+ ending to get it and then use it on your next time through in all the place above to unlock the alien ending.

Voilà, je le mets au cas où ça serve à quelqu´un.