5.3.0a1 Lua Errors "ButShowOnMap" and "nil value"

[Vetinari]

I'm often getting two Lua Errors. When I first install a fresh copy of Carbonite, after cleaning out all the Carbonite files, it works fine. When I return to the game, I get the errors in these two images. I am using the enUS client.

The error in this screenshot only appears once:
http://i.imgur.com/0s3guzW.jpg

The error in this screenshot continuously counts up, but strangely, doesn't seem to affect gameplay.
http://i.imgur.com/G3AtpFd.jpg