This puzzle is a 4x4x4 cube with rotations.
It's not an extremely difficult puzzle, but a quite tricky.
The fitting of the single little cube is very tight.
When you assemble it, you just have to push this single cube.
When you disassemble it, you DON'T have to use force, flexibility, or shake the puzzle.
There is a trick way to get out this single cube.
With those informations there are two levels :
Assembling : 18 (9,7,1,1).
Disassembling : 22 (1,5,8,9).