That's how it is for everyone, not just beginners - 5 files max, 20mb max each.

I think it depends a lot on the type of designs you make. For certain types of sublimation, these little imperfections are not going to be noticeable. For example, if you make a mug wrap, unless the character is especially large, the toes aren't even going to be that visible. Also, AI differs a lot in terms of quality (and these errors too) from one generator to the next. Kittl, Dall-e3 and the free Bing Image Generator are the best (in my opinion) at producing error-free images. Ideogram does a good job as well and sometimes even Flux, but these two maybe work only for print on demand - for sublimation they are extremely unimpressive. At the same time, clipart has the downside that it's always isolated on a white/transparent background, so if people really want to find something wrong with your design, they'll find the defect a lot easier, especially if it's overlaid on the white. I have almost completely stepped away from clipart and PNG designs (for t-shirts and so on). It can be practically impossible to produce a perfect image for that purpose, unless you want to use Photoshop 100 times a day. Plus, when you sell them with a transparent background, if the background remover doesn't do a good job, you either go back and generate extra images until you come up with one whose background is easy to remove or you can spend hours upon hours in an editing software manually fixing the imperfections. To answer your other question, I think most people are ok with imperfections so long as they don't use the image for a large item where the imperfection becomes this huge, horrible thing. I started out my shop with PNGs for t-shirts and SVGs and I gradually switched to sublimation crafting for multiple full-color, full-background items - tumblers and more. Very, very rarely do I post something with a transparent background these days or made for printing/sublimation on a large item.

@Melanie Parent well, I literally didn't notice the things you pointed out until you did. In my honest opinion, the first image looks adorable and would pass as a great one to Etsy buyers as well - perhaps the hat might've been something to fix, but even the tail looks absolutely adorable. With these pseudo-antropomorphic animals or glittery animals that have something to do with a holiday more than they do with their anatomical or historical accuracy, I believe you can bend a lot of rules. I am pretty picky myself, but if you look at some hugely successful sellers on Etsy, you'll find errors in designs that have sold hundreds of times and people haven't even noticed that there's a SPELLING error in there (which I think would be far more unforgivable than a hat that's slightly weird). :) so I think that you're doing great and that stuff that bugs you will most likely not be noticed by the majority of buyers.

Did they reference the order number? Look in your "Orders", in the "Completed" section to see if you can find the purchase there.