What steps will reproduce the problem?
1. Level a character from 79 to 80
2. _Don't reload UI in any way_
3. Mouse over TitanWG

What is the expected output? What do you see instead?
One would expect to see the usual popup. However, since the player has just reached the level requirement for VoA, the popup tries to display the uninitialized VoAData entry for the player.

What version of the product are you using?
1.1.5, but comparing the code interacting with VoAData it still seems to be there for 1.1.6.4.

Do you have an error log of what happened?
Attempt to index '?' at line 373: nil.
Rephrasing that to 1.1.6.4 that would be line 391.

Please provide any additional information below.
This problem can be fixed by an extra check inserted before line 391:
if not VoAData[TitanWG_realm] then
    VoAData[TitanWG_realm] = {}
    VoAData[TitanWG_realm][TitanWG_player] = {}
else if not VoAData[TitanWG_realm][TitanWG_player] then
    VoAData[TitanWG_realm][TitanWG_player] = {}
end
This code has not been tested, mainly because I don't reach level 80 every day :D.