oh... hm .... that wasn't really what I thought of

And yes, everything is setup correctly and I can't store the
key items in the chest, but they are not grayed out (in the "store" window).
My original suggestion was to gray out items that you want to store in the chest,
but which are "key items".
So that, for example in my game ( yeah, I'm a selfish bastard, sry

), you can't
store the "diary" in the chest, because you need to always have it in your inventory
and so it's grayed out in the "store" window.
Would be cool if it also worked this way...
but thanks for the explanation