Please include as much of the following information as possible to help me fix the bug:

Brief Description of Bug

An error happens when interacting with some currency vendors.

Steps to Reproduce

Buy an item from a vendor for currency.

Loaded Addons

Include a list of addons you were running at the time this bug occurred.

Back Trace (LUA Error Output)

2x Journalator/Source/Utilities.lua:68: attempt to call field 'GetCurrencyListSize' (a nil value)
[string "@Journalator/Source/Utilities.lua"]:68: in function `GetCurrencyID'
[string "@Journalator/Source/Monitor/VendorItems.lua"]:432: in function <...ceJournalator/Source/Monitor/VendorItems.lua:417>
[string "=[C]"]: in function `BuyMerchantItem'
[string "@FrameXML/StaticPopup.lua"]:280: in function `OnAccept'
[string "@FrameXML/StaticPopup.lua"]:5235: in function `StaticPopup_OnClick'
[string "*StaticPopup.xml:24_OnClick"]:1: in function <[string "*StaticPopup.xml:24_OnClick"]:1>

Locals:
currencyName = "Stone Keeper's Shard"
index = 0
(*temporary) = nil
(*temporary) = "attempt to call field 'GetCurrencyListSize' (a nil value)"
currencyMap = <table> {
}

An easy fix is

local GetCurrencyListSize = _G.GetCurrencyListSize or C_CurrencyInfo.GetCurrencyListSize

at the top of Utilities.lua for example.

Thanks for the report. I haven't been able to test the currency tracking on Wrath - lacking a character with the right level, location and inventory to do it - so missed that case.

Can you try this version?
Journalator-1.38-1-g10368f4.zip

Seems to be working fine.

In the current Wrath Build if it's any use

Thanks. I've added the fix to the next alpha release (pending build scripts and processing by Curseforge or Wago)