As I left the message on slack, here is the error I get trying to put something on the sell tab. Looks like a few more tweaks are needed to item classes.

Buy seems to work great and no errors on launch or reload so super impressed you patched something together yesterday.

Auctionator\AuctionatorLocalize.lua:354: attempt to get length of local 'itemClasses' (a nil value)
Auctionator\AuctionatorLocalize.lua:354: in function Atr_ItemType2AuctionClass' Auctionator\AuctionatorLocalize.lua:295: in functionAtr_IsClass'
Auctionator\AuctionatorLocalize.lua:270: in function Atr_IsGlyph' Auctionator\Auctionator-4.0.0.lua:4420: in functionAtr_Special_SP_ByItem'
Auctionator\Auctionator-4.0.0.lua:4374: in function Atr_GetStackingPrefs_ByItem' Auctionator\Auctionator-4.0.0.lua:4453: in functionAtr_GetSellStacking'
Auctionator\Auctionator-4.0.0.lua:3000: in function Atr_OnNewAuctionUpdate' Auctionator\Auctionator-4.0.0.lua:194: in functionAtr_EventHandler'
[string ":OnEvent"]:1: in function <[string ":OnEvent"]:1>
[C]: in function ClickAuctionSellItemButton' Auctionator\Auctionator-4.0.0.lua:1548: in functionAtr_ClickAuctionSellItemButton'
Auctionator\Auctionator-4.0.0.lua:1565: in function `Atr_OnDropItem'
[string ":OnReceiveDrag"]:1: in function <[string ":OnReceiveDrag"]:1>

Locals:
itemType = "Tradeskill"
itemClasses = nil
(_temporary) = nil
(_temporary) = nil
(_temporary) = "Atr_ItemType2AuctionClass"
(_temporary) = nil
(_temporary) = nil
(_temporary) = nil
(_temporary) = nil
(_temporary) = nil
(_temporary) = nil
(_temporary) = "attempt to get length of local 'itemClasses' (a nil value)"
zc =

So not sure if this is good lua coding, the right wayto do this, making it primed to explode later or not but it seems that trying to define the length of itemclasses isn't working because there is no table to build something to grab the length of (hopefully my poor explanation skills makes sense - defining itemclasses as a table lets you # it later).

I changed line 352 to this

local itemClasses = { Atr_GetAuctionClasses() };

and low and behold we got what we needed in #itemclasses and no annoying errors and the code seemed to run as intended in the sell window. Not sure if it will break or not but at least that moved it forward.

Just tried every GUI options and no errors. I think you got this working (with the one small fix I just did).

You fixed this one, too, thanks!