I just received a "419 | Page Expired" error when trying to use the <- Switch to Legacy System button on the opt in/out page provided in the OP.
im having the same issue as Truffula- body parts stay visible when turned off :/
art by
Current list of issues with kumos wardrobe on 12/7/2025 - found while building an outfit. In order of priority to fix in my opinion:
Previous issues I didn't test this round:
I tried to record a video of the layer selection problem in wardrobe, showing that the items shown don't change when I select a different layer. I used "LICECAP" and it made a gif. Going to try to upload the gif using your image thing. 
That worked great, so for my next demo, I will show how it ignores the selected layer and just shows cached results. Like, I got the results for new on site with Bottom as the selected layer originally, so no matter what layer is selected, when I change to that sort order, it just shows Bottoms. See the gif below.
oh shoot, it wont upload it because it's bigger than a MB. alas. let me try something else.

yay, giphy worked! (I hope) Meanwhile you can also see the "item #" broken image issue on this gif.
As requested, I'm going to post what I stated here, that way it's easier to follow!
now that i'm trying our beta wardrobe on Kumos, i'm noticing a few, issues, that i didn't on a cursory glance last night.
the inability to collapse the sidebar down means adjusting the layers of an outfit is brutal (plus the items don't show up as themselves on the layer feature) the fact that the layers are in reverse to the new.subeta one (instead of highest layer= the one on top), the lowest layer= the one on top, which is messing with me!) some labels and tags work, some just don't (i imagine that's an easy fix in due time but, yeah, it's inconsistent and messy haha) obviously the inability to preview items you don't own is really bad lol (that's literally how i make outfit refs for my characters and look at things to see if i want to buy it ) also the inability to try salon styles you don't have is also a negative rn (plus tyhe old default hairstyles are completely inaccessible now)
However, i do want to acknowledge what I like so far, as while this is obviously a WIP (and it does need some fixes), there is some changes i really like
some positives i'm really liking with this new wardrobe:
regarding selectable hairstyles, it does tell you how many highlight layers it has, that's pretty awesome! the effects board? that is hella awesome, and i'm just imagining all the things you can do with that in the future! (even what it's got now is pretty awesome!) i love the new ordering tags! i very much enjoy the way items are spread out (easier to not misclick now!) all the new tools make things a lot more convenient! the large plethora of bug fixes that have been implemented oh and before i forget: i am really enjoying the potential of the new outfit page
"Even though I may only meet you where heaven and Earth collide, your warm touch and fanged smile bring me comfort. I may burn in hell for loving you, but I would rather burn alive than spend a single day without you. Even if I choose to be alone in this world, I know you're there for me in the Eldritch beyond. In a way your Demonic origins allowed you to sense my pain, and you always find ways to show me you care. Your love is genuine, and for that you shall be my mate. May Artemis guide us"
coming back to test again:
tried Asa hair in salon in test - it only let me set main color, shadow (dark) and shadow (light) but ignored the settings for shadow (dark and light both). It let me set 2 of the 6 highlight colors, ignoring the ones it wouldn't let me set.
Couldn't import legacy outfits, pressed the button, the page went blank, waited half an hour, nothing had loaded.
The main change is a (from my POV) negative one: I can no longer use the kumos wardrobe when not "opted in" and it displays my legacy HA on kumos when I'm "opted out" - originally it would show my kumos HA on kumos and my legacy HA on legacy (which was more fun for me but I get why maybe not the intended behavior)
I just went to go check this out, and started by trying to migrate my outfits--for some reason, some of my outfits are duplicated a huge number of times, and many are missing (as if the duplicates overwrote the old outfits.) I don't want to do anything with the new wardrobe until I can confirm I won't be deleting or replacing any of my outfits from the new.subeta.net wardrobe.

they/them/theirs, please.