I am also having this same issue since updating my game with the latest patch.
I removed all mods/cc, cleared my cache, repaired the game, then factory reset my game folder. Can confirm this issue only happens when I use an existing save and attempt to enter bb for any lot from the map view.
Not sure if it's related but my game has been generating a last exception each time the error code pops up. Seems to be something to do with unidirectional relationships and possibly a trait. The last exception appears the same with and without mods/cc.
