I reached level 8, and Cyrus gave me the Wumpus quest. I went to the library and found out it didn't exist. I left the library to return to Ravenwood. My game crashed - I got a message asking if I wanted to report an error. I did report.
When I got back to Ravenwood, I realized my wiz is now level 7. I restarted wiz, no change. Restarted the computer, no change. Cyrus gave me the next quest step so my game is hopefully OK.
I have screen prints showing that I have the quest (level 8) and current status as level 7; I don't see a way to insert those.
the title saying I lost all stats was inaccurate. This is a low level wiz and only stats are health/mana
Open a support ticket to get the issue looked at. There isn't much that can be done via the forums other than suggesting you do that. There are times when the information for a wizard gets a little messed up, and the only way KI can address it is via a support ticket.