Yes it makes sense to have a "friend" who takes over, but my problem is that I gave an event to convert estate to village. Do you remember the peace campaign when you have to rebuild a ruined castle? You move to that estate while your old one becomes YOUR village, not a neutral one. I tried to do the same, but I can't.
Taken enemy castle always remains intact unless you playing kingmaker or you add a trigger to convert it into an estate.
Btw, did you know that building sites can serve as variables? I made an optional quest to take out outlaw camp and by doing so, outlaws become available for you. But every new mission requires manual addition of unit types should your available army changes. So, if you destroy the outlaw camp, the later change will exclude your well earned outlaws (you can't destroy again the already destroyed camp), unless you add them, which kills the optional quest's purpose.
So I found that adding a dummy building site, I can keep outlaws optional. For example, I set building site inactive (so monks won't mess it up) and give it 0%. If you destroy the outlaw camp you give a trigger to set building site to 1%. Since rebuilding it via monks is no longer an option, you can only achieve the 1% by destroying the outlaw camp. So giving instead a trigger that "if building site is 1% then set available unit types" and you add outlaws, you can keep this quest optional.
Ps: I tested the runes of wisdom's castle change. It also have the neutral estate issue.
[This message has been edited by Cortez2000 (edited 02-17-2017 @ 09:38 AM).]