Please just use one thread per game. This way we can follow your gameplay and possibly help you better. Also it doesn't push another thread off the first page.
I deleted the other thread you started.
Are you talking about the gargoyle at the corner? The clue here can be found by counting the comets at the Corbin coat of arms.
Box in Nancy room will be opened by studying the star chart at Nancy's room and Bridgitte's coat of arms.
The lightning bolt and the clock will be needed later in the game.
It is best that you do the gargolye puzzle at the corner, then continue on with the series of puzzles that follows that.
Then you will find the other side of the triangles that you asked earlier.
There's more to do before you can gather all the clues.