I believe this messes with the Dynamic Bag Upgrades mod, whenever I upgrade my bag sizes for any of the items you've made wearable it'll pop up with an option to fix it from the DBU mod; in context menu, even doing that sometimes it'll still show red for items that I'll want to put in there but they'll still be moved. The biggest thing is the compatibility, it also makes it so certain items I can't even put in these containers anymore. Like the toolbox, completely ignores sledgehammers now and the sewing kit won't allow me to place the military straps from the DBU mod into it anymore. I'm sure there's more but I've got like 190 mods for B42 so I'm sure other things may be affecting it as well lol.

Solid mod though love the idea, and I use multiple other of your mods and they work fine so far; other than the can sealer one can't get that one to work with what I've currently got installed, just doesn't popup at all in game.

I am not responsible for other mods. If you use multiple mods manipulating the same bags, it is absolutely normal to encounter problems. It‘s like you want to wear multiple schoes in real life, the more shoes you wear the harder it gets to wear em.
Place decide what mod you want to use and stay with that mod - one for bags and one for whatever else etc.

When "wearing" a pencil case the 3D model is superimposed in a large silhouette around the character where bits of the (super huge) model are clipped around the character in various states of see-thru.

*(you can even see it in character create if you Sandbox allow all and add Pencil Case then rotate enough to see the model off to the side and not quite as large)

Thank you for taking time and writing the Feedback!
This definitely has to be a bug of the new build.
Hiwever, I’ll wait for the stable release, then I will update all my mods.
Since the new builds there are tons of new bugs so it just makes no sense to me to put in more effort for now.