Dutch Blitz Vert. 3x4 Box 2-12 Player w/ Note Slot

I remixed a 6 slot Dutch Blitz box to fit 8 decks plus the instruction sheets, but this weekend I played with my family and I now need the 3 decks (Blue, Green and Purple) in a single place, I think I optimized the size by placing the decks vertically. It also has a slot to keep a pen and scoring sheets. I kept a 5mm thickness of the dividing ribs so decks are easy to take out either by the sides or by the front and back.

I personally haven't played a game with 12 players, and nowhere have I found in the rules that it is allowed, but why else would they release another expansion?

I still haven't printed the scoring sheets, They still have to be worked on so they fit well.

The inside dimensions for each deck slot are D:15mm W: 60mm H:85mm since there seems to be a version of the game which doesn't fit inside my design.