I normally publish and update all my models at MakerWorld. They are only here on Printables to keep the accounts consistent.

Please download the newest version here at MakerWorld – including print profiles for Bambu Lab printers.

Harder than I thought. Put all 25 pieces in the cube holder.

Just print the puzzle piece 25 times  and the cube holder once.

No support needed. I used 2 walls and 15% infill.

I uploaded a pdf with one possible solution as proof that it's solvable.