Despite Curse doesn't deal damage on initial cast when it used in time when target cast Cloak - it remove Cloak. It make Cloak in Cyro even less reliable since every sorc use Curse.
Looks like a bug, cloak should only be removed by the curse explosion, like it always has.
TBH I haven't noticed it doing this, plenty of nightblades have cloaked on me with curse still cooking on them.
The thing is when you can easily counter Cloak by casting instant damage ability at the same time when nb used Cloak - it would pull nb out of it instantly:
But Curse is not dealing any damage on cast yet it still making removing Cloak.