I also get the problem with the buildings tab (no wonders tab at all) and specialist area. (Same as SlothACID's pic above).
It extends to spies as well - you can see what the enemy civ is producing but not the city's buildings, wonders, etc.
This just happened to me inmy capital. Had some buildings and the Pyramids wonder.
Lua.log (attached) has a lot of errors that didn't appear earlier in the game.
\Skodkim