I can tell you that Lucid Dreaming doesn't restore mp if you're in Astral Fire (All mp restoration is disabled by astral fire) and if you're in Umbral Ice, you restore mp so fast you won't really notice the mp restore from Lucid Dreaming. This has always been the case. Is it not restoring mp while you're not in either stance? (To be fair, it's an innocuous bug if that's the case because the ability is just straight up useless to blm anyway because of Astral Fire/Umbral Ice).