1st game, still going.
I crafted Cloak of Shadows for Tandis. It was his chest armor for several turns and a few fights.
Then ... it vanished. It is not on any unit, nor in my inventory. It simply disappeared (and Tandis's chest armor slot was empty the next time I looked at it).
- I may have done a few Quit/Load iterations. The save file (I have only one) did have the Cloak in it at some point.
- I didn't notice any combat effect that destroys an armor.
I conjecture that this is just a Load bug.