Vorpal Strike is a bit of a mysterious one at the moment. I've not at the time to fully test it out but I have bugged it into the Dev's Bug Report with what I've seen and tested so far:
1. Vorpal Strike correctly applies the Slashing property to Handwraps.
2. It does not provide you any Vorpal capability however (Rolls of 20 just produce a crit)
3. During transitioning and some resting (unsure on which or both or more, as I've not had time), your "hands" become reset to a basic magic, bludgeon DR breaking of the basic Hand Wrap design. ie. You lose all properties that would let you bypass any other form of DR. Swapping Hand Wraps will resolve this until the next time it "resets" again. Personally, I'd just repeat at the moment every time I transition or rest until it's been examined more closely by someone.
The likelihood was you lost all the effects (Good, Slashing, Silver, etc) when you went through and only was hitting with a basic enchanted club, rather than the leathal weapons that they should be.
J1NG
:: edit ::
Nevermind, I've just confirmed what I've written here with a quick test. VoN3, on entry, lose all Unarmed Silver, Cold Iron, etc from Monk and Shintao. Chaning Handwraps restores all missing effects. On Resting or Transitioning, the Hand Wraps will revert to their unequipped weapon types (Bludgeon, with Magic, Good, etc that are on the Hand Wraps already, every other weapon type for DR bypass else is stripped from you).
So the "fix" for now would be to change Hand Wraps or to unequip and re-equip. Although lets be honest, you can't be running around with just one pair of wraps. I've always had a couple to swap around into.
