... not sure about the completion. Let me try to explain.
After I completed it and was going through to do the puzzle, I wasn't sure if some of the places the marble was to go and didn't fit was meant to be that way, or I had actually put it in the cube wrong or something. It was a little confusing to me.
As for coloring it, I used regular Sharpie markers, but I was using the 6 color palette and I knew ahead of time that it would bleed in, but it worked out since I was just using one color per piece. I plan on trying to get another level one when I can afford it just to try and do one that would have a picture on it like the pumpkin or the ghost.
Overall, I enjoyed putting it together. It was very relaxing for me and thank you for your time in creating this