I own several castles and recently bought the Winter Wind Tower. I've managed to replicate the bug's trigger on certain conditions.
The Bug: Teleporting via Magic Mirror to any of the two outside areas (Duel Circle and World Door) boots your from the Home and yields the error: "The house that you teleported to has been sold."
The Trigger: Clicking the 'Go Home' button while having another Castle equipped and using a Teleporter Pad to get to Winter Wind gives you the error. A wizard must have the Winter Wind Tower equipped from the start to avoid this bug.
Hope we see a fix soon, as I like using my proxy house as a hub to all my homes
