*Ah ha!!!!, I found the site again.........you can find their template HERE, at Paper Scrapz. And *said sheepishly* it is called a Keepsake Box...not Treasure Box like I thought (I'm only 39 and my memory is already going *sigh*).
The Stationary Box is made from 2 pieces of CS...the 'box' is made from one piece, and the 'cover' which wraps around the box is from the 2nd piece.
'Box' Piece: I cut it from CTMH White Daisy CS (the photo isn't true colour). The dimensions: 8 1/2" x 9 3/4". Piece A
'Cover' Piece: This is also cut from CTMH White Daisy CS. The dimensions: 6 1/2" x 12". Piece BI covered the 'Box' Piece with CTMH Serendipity B&T Paper. I made it 1/2" larger on all sides so that I could wrap it around the CS and give it a nice finished look. Dimensions: 9 1/2" x 10 3/4". Piece C
Because the 'Cover' Piece is already 12" long, I cut 2, 1/2" strips to glue on the back side, to keep the uniformity of the look. (Clear as mud???) Dimensions: 7 1/2" x 12", 2 strips: 1/2" x 6 1/2". Piece D
Now because I wrapped the B&T paper around my 'Box' and 'Cover' base pieces, I wanted to cover the backside to give it a nice finished look (I used the thinner pattern paper for this, not the heavier CS...because eventually this 'sandwich' has to be folded)....these pieces are a 1/2" smaller on all sides than the base CS pieces....The pictures farther down help explain my madness!! Dimensions: 8" x 9 1/4". Piece E
Dimensions: 6" x 11 1/2". Piece F
Okay, now for assembly!!!
This is the 'Box' Piece-Piece A. I Tombowed (is that a word?) the corners, because I did not want the covering pieces to 'bubble' after I glued them on.
Piece A glued on top of Piece C, and the corners cut.
To cover the 'Cover' Piece, I glued the 'Cover' Piece (Piece B) onto the pattern paper Piece D.
'Cover' Piece: Score 5 1/16" from the short side.
And that's it to making this Stationary Box....I like to err on having too much information than not enough, so hopefully I covered all your questions, if not feel free to ask.