Starting with the cylinders around arbitrary minor axes, for the first hundred or so you were demonstrating a notable issue regarding the relationship between the ellipses at either end, and which one you'd fill with hatching. As noted in the instructions, the ellipse closer to the viewer is both larger in its overall scale, and narrower in its degree, than the ellipse on the far end (which conversely would be smaller in its overall scale due to the convergence of the cylinder's side edges, and wider in its degree).

For the first hundred, it was unclear which side was meant to be which, as you got these relationships mixed up. As we can see on this page for example, the ellipse with the hatching (which I premise was intended to be closer to the viewer, based both on the hatching and the arrow heads on your minor axis lines), was generally drawn smaller than the opposite (farther) end. This quite directly contradicts the core principle of perspective, that as things get farther away from the viewer, they generally appear smaller. Instead, the far end should still be proportionally wider, as it is now, but the overall scale should be smaller (which is unavoidable if we have the side edges converging in that direction).

Now, after that first hundred, you appear to have picked up on this problem, and corrected it. We're fortunate that you did, as this would have resulted in some significant revisions. I would still recommend that you reflect on why exactly you were making that mistake - mistakes are of course normal, but this is one that would have had to do with a core principle of perspective that should at this point be fairly solid.

The other point I wanted to call out in regards to this part of the challenge is that your linework suggests (and this may answer the previous question as well) that you are not taking as much time as you should be in your work. That is to say, you appear to be rushing. I'm not seeing signs that you're properly applying the ghosting method to each and every freehanded mark, resulting in side edges that while being mostly straight do waver in ways that suggest a slightly hesitant execution, rather than the confident one that the ghosting method requires. I do see the start/end points that are hallmarks of the planning phase, so you're at least applying part of it, but it is very important that you remember the overall purpose behind the ghosting method - to break a complex task into distinct, simple stages, each with their own priorities.

As an extension of that point, make sure that you're also engaging your whole arm from the shoulder when executing your ellipses, and that you're ensuring that you're drawing through them two full times and not stopping a little short. That's something we see from students when they get a little careless, going through the memorized motions but not necessarily considering what choices they're making and what actions they're taking throughout the course of their work.

Continuing onto your cylinders in boxes, along with the similar signs that you could definitely be investing more time into each individual mark (specifically the planning/preparation preceding their execution), I am also seeing another significant concern.

You are frequently extending one or more sets of lines in the wrong direction. For example, 204 and 205 on this page both have their red lines extended towards the viewer rather than away from them. Similarly, 220 on this page has its blue lines extended incorrectly, as does 225 here, and on 226 here the red and blue lines both appear to be incorrect. There are many others, suggesting that this is not just a once in a while issue, but rather a more significant concern. These notes from the box challenge explain the concept of lines being extended in the wrong direction, and the section below that one explains an approach you can use to guarantee they'll be extended correctly without requiring you to understand the underlying concepts. I will note however that the expectation is that the student will have incorporated the freely rotated boxes with line extensions from the box challenge into their warmups, so this issue coming up here does raise questions about whether you've been iterating on the previous concepts and exercises as you were meant to.

Continuing on, I also wanted to stress that you should keep your line extensions - that is, which belongs to which larger set - consistent. There are situations where a box can end up coming out so narrow that the minor axis ends up oriented towards a different vanishing point than the one it's meant to. We can see this in 221 on this page for instance, where the minor axis would match up roughly with the red contact point line. From what I can see the (blue) minor axis lines were never actually drawn, and the result is that this case appears to be entirely correct, even though the minor axes are nearly perpendicular to how they should be oriented. Make sure to actually draw the blue line in, so that the error is obvious and difficult to overlook. That is ultimately how this exercise works - we draw boxes, we draw ellipses in two opposing faces such that they touch all four edges of their enclosing plane, and then we apply our line extensions. Any discrepancies in the alignment of those line extensions from their corresponding sets from the box's edges are signs that the proportions of those opposite planes are not quite square in 3D space, and so we can make adjustments to bring them more into alignment for the next set. If however we aren't aware of the mistake, then we aren't in a position to address it.

Going back to the point about your linework feeling rushed, I did take a look at the timing behind your submissions, and upon realizing that you submitted pretty much as soon as the system would have allowed you to (in regards to the cooldown between submissions), it becomes rather clear that you did in fact rush and neglected to uphold your end of the bargain - that is, what is expected of all students in their efforts as they work through the course, if they choose to take advantage of the heavily subsidized official critique track. I urge you to review this video, but the jist of it is that it is each student's responsibility to take as much time as they require to do the work to the best of their current ability. That means giving yourself enough time to review the instructions, and in giving yourself as much time as you require to execute each and every mark to the best of your current ability. As explained here it's pretty common for students to modulate how much time they spend on a given mark based on the complexity of the overall task at hand. In this course however, we insist that every student do the opposite - that regardless of how complex a task is, or how much time you have to complete it, each mark still gets as much time as it needs, and everything else extends off it. The outcome is usually that the work takes more time, but that's pretty much how we can offer feedback as cheaply as we do - by putting the bulk of the labour on the student. To that end, my feedback becomes a lot less valuable and useful if you're not already pushing yourself to your limit.

All that said, I'm going to assign some revisions below. The revisions themselves are assigned based on the issues with your cylinders in boxes, but their quantity is increased on the basis of your rushing - so in the future, refrain from doing that.