Raze_Larian: Gold can be taken from other party members when you use the balance icon when trading. A few skill books, etc, could have cleaned out the character.
Do you have previous saves to reload? Narrowing down when it happened may help determine what happened.
Did you check containers you may have dropped or sent to the homestead, etc, before you noticed the gold was missing? There is a pouch container with the same icon as a pouch of bonedust or moondust.
It happened while I had the savegame of my friend and tried to solve the problem with the death knights, as described in the other thread. And probably at some point when I went back to Silverglen and bought two Walk in Shadows skillbooks, and maybe one invisibility potion. My other characters still have the same amount of money they did before, but that character who carried the 10.000 now has 0, instead of a few hundred or thousand gold less. And I can't imagine that I gave a merchant more than his items were worth, but I have no other explanation either ... (I also think I would have noticed that, since it would have given me a popoup with lots of Attitude bonus from that merchant ;) ).
The thought with the homestead occurred to me as well, but AFAIK I didn't ever use this function during that period. Dropping containers - dunno, could be, I occasionally pick up random stuff in the environment by accident and tehn drop it again, although I don't know how money would have gotten into it. If something like that happened at all, it was probably just an empty basket or so.
I guess we'll have to try that CheatEngine, thanks!