Hi June,
I don't think it makes a difference if you put the tetrahedron in slightly earlier. Here are directions from MaG's walkthrough:
Go around the path that surrounds the Sacred Rings. See 4 stands with buttons on inner balconies.
At the front of the Sacred Rings, there are 2 stairs that goes up to a platform. Climb the stairs and see a lever.
Go down the stairs across from the door and see a metal case at the base of the Sacred Rings.
Using the library book pictures entered in the journal as guide to power up the sacred rings.
Go around the Sacred Rings and program the stands based on the stand pictures. Press the buttons that are shown by the shaded circles. The circles in the drawing are as you see the circles on the stand facing you.

Hope that helps.
