Reported from the comments section
http://mods.curse.com/addons/wow/auctionator?comment=5929

Version 4.0.0

Interface\AddOns\Auctionator\AuctionatorHints.lua:242: attempt to index field 'DisenchantingProbability' (a nil value)
Time: 07/19/16 19:35:27
Count: 41
Stack: Interface\AddOns\Auctionator\AuctionatorHints.lua:286: in function Atr_CalcDisenchantPrice' Interface\AddOns\Auctionator\AuctionatorHints.lua:359: in functionAtr_STWP_GetPrices'
Interface\AddOns\Auctionator\AuctionatorHints.lua:441: in function Atr_ShowTipWithPricing' Interface\AddOns\Auctionator\AuctionatorHints.lua:498: in function <Interface\AddOns\Auctionator\AuctionatorHints.lua:496> [C]: in functionSetBagItem'
Interface\FrameXML\ContainerFrame.lua:1059: in function `UpdateTooltip'
Interface\FrameXML\GameTooltip.lua:241: in function <Interface\FrameXML\GameTooltip.lua:225>

Locals: classID = nil
itemRarity = 3
itemLevel = 1
dePrice = 0
Atr_FindDEentry = defined @interface\AddOns\Auctionator\AuctionatorHints.lua:241

Unable to reproduce, will close if we can't get more information (added a request for more info in the comment on curse).

Closing until we can get details to reproduce.