It is good to know that after a year you stil have not fixed the problem with "Build Def. Works" fails after the Xth time it happens.
I would paste the log except the game has the worst log reader in the history of log readers. I would post a screen capture or the game files but that does not seem possible in the new forum.
PS. It is not a nVida Conspriacy. The Video Driver is not no counting the times "Build Def. Works" is done and displays the error message when the Xth "Buld Def. Works" is done. It is because an array goes past its upper bound.