hey,

indeed, to enter the monastery, the "golden key" has to be either in inventory or holding it on mouse or someone having it equipped (in hand).

Hmm, that sounds like an issue. Are you using the "Prelude" version (paid) and 1.4 version (shown on title), right?

If that happens always, could you send me your save.dat file with that save just before entering monastery, on my e-mail: burzum_mewtwo@yahoo.gr

so I can take a look. Can't think of anything at the moment, but usually its either a corrupt save or data issue on game's database.