I had a great time assembling the puzzle, instructions were super easy to follow and everything came together well.
I did notice a slight error on step 126, the instructions say the round part comes from sheet C, but the part was actually on sheet E
Also the holes on the acrylic sheets are too small. I had a lot of trouble getting it together and ended up breaking quite a few of the holes. I ended up having to sand down the tabs in order for it to fit, end even then, holes were still breaking. You might want to consider increasing the tolerance just a hair. The holes on the Level One puzzle, however, were perfectly sized, so maybe the holes for that one had slightly higher tolerances?