For the first 50, your lines are clean overall. However, I did see some wobbling throughout the set. Your convergences also show good accuracy, though I did see some lines veer off in the wrong direction, like in box 9, box 27, and box 49.

For the next 50, your lines show improvement. Wobbling is still present, but instances grow less dramatic throughout the set. Your convergences also show improvement in accuracy, though there are a few more instances of errant lines, like in box 56, box 68, and box 87.

For the last 150, your lines continue to improve, with wobbling growing further reduce towards the end. However, since it was present throughout the challenge, I do recommend reviewing the information in this section to ensure that you're practicing the proper technique.

Your convergences also continue to improve, with errant lines further reduced. However, I did see some instances where lines pair off towards two vanishing points, like in box 114, box 175, and box 239. In these boxes, the inner lines (green and orange in this diagram) diverge instead of converging at the vanishing point. Keeping in mind the angles of neighboring lines can help when planning the box's construction.

I did see a few points where lines appeared to be drawn over multiple times, like in box 99, box 130, box 166, and box 218. Some of your notes indicated that there were attempts to add line weight, but I want to remind you that, for this exercise, it's better to have one smooth, confident line than to correct it by redrawing. Adding line weight is fine, but take care to avoid a situation where it looks like the lines were redrawn or scratchy.

Regarding the missing back corners, it's not an issue since you caught and corrected it yourself. I did see that the boxes on this page are missing some other line extensions. However, it wasn't a common issue. Just be sure to double-check that all lines are extended going forward.

All said, I'm going to mark this challenge as complete.