Requiem Shard

I've tried a few times but when adding a "container lock" to fancy chests I'm unable to unlock it with the key that spawns in my backpack.

I've tried within the pack, on the ground next to me - nothing seems to work.

you try that just by clicking once and then Lock/unlock via context menu?

Derp.

That worked! I forgot your can't target these chests with keys. Thank you sir!