Jumping right in with the cylinders around arbitrary minor axes, your work here is by and large quite well done. You've tackled a wide variety of ranges of foreshortening, and I quite appreciate the way you've mixed up the contents of each page (in terms of varying the foreshortening, orientation, length, all that good stuff). The way you've approached it helps a lot in avoiding you falling into the kind of auto-pilot that can result in mistakes and missed opportunities for learning.

Your linework is largely quite confident and well executed, and I'm pleased to see that you've been fastidious in checking the alignment of your minor axes, catching both more obvious issues as well as those subtler ones that can be easily missed.

For the most part you seem to be demonstrating either a conscious or unconscious awareness of how both the shift in scale and the shift in degree from an ellipse on one end of the cylinder to the other behave together. Since they represent the same thing (how much of the cylinder's length can be measured on the page vs. how much exists in the unseen dimension of depth). That understanding - which I suspect is more subconscious than conscious (hence why I'm explaining it) - generally shows in how you tend to match an increasing scale shift with a similarly increasing shift in degree. Or in other words, where the side edges converge, causing the far end to get smaller, it should also cause it to get wider.

There were a few places where I wasn't seeing this as prominently, so I wanted to just quickly make a point of it - we can see this on this page where the far end on 123 and 124 could stand to be a bit wider (especially 124). Conversely, 125 is an excellent example of the degree shift being applied in measure with the scale shift.

Continuing onto your cylinders in boxes, I was very pleased to see that while you started out on the wrong foot, you seemed to catch yourself and correct the mistakes by the time you hit 180, allowing for a pretty significant part of the challenge to still be tackled correctly. This exercise is really all about helping develop students' understanding of how to construct boxes which feature two opposite faces which are proportionally square, regardless of how the form is oriented in space. We do this not by memorizing every possible configuration, but rather by continuing to develop your subconscious understanding of space through repetition, and through analysis (by way of the line extensions).

Where the box challenge's line extensions helped to develop a stronger sense of how to achieve more consistent convergences in our lines, here we add three more lines for each ellipse: the minor axis, and the two contact point lines. In checking how far off these are from converging towards the box's own vanishing points, we can see how far off we were from having the ellipse represent a circle in 3D space, and in turn how far off we were from having the plane that encloses it from representing a square.

Where you went awry is that before 180 you didn't seem to be following the instructions correctly, and were neglecting to apply the contact point line extensions. Beyond this the only other issue that was present, and that did persist through the rest of the set (but fortunately wasn't as significant, but still should be corrected going forward) is that when you identified the minor axis lines, you did not extend them all the way back with the other lines. I imagine you may have confused it with how the first section is completed, and may not have paid as close attention as you could have to how it was demonstrated for the cylinders in boxes exercise. The reason we want to extend those lines all the way back, along with the others, is to give us the easiest time assessing where the alignment is off at a glance. The more it is extended, the easier this becomes.

Aside from that, solid work. I'll go ahead and mark this challenge as complete.