Nostalrius Begins - Quality wow vanilla realm (1.12)

When I click on most NPCs I crash, including some quest-givers, plainstriders, other players, and a dead cougar
The only NPCs I that haven't crashed me when i've clicked on them are a quest-giver and a cougar.
Thanks!

Greetings.

Tried to reinstall your client ?

Delete all client files and follow the toturial in the link below
viewtopic.php?f=6&t=638

Bugs should be posted in the BugTracker System