[Fizzlemizz]

Also, for future reference, if you want to pass information between modules (.lua files) within the same addon, each .lua file is "passed" two parameters, the name of the addon and a table that is exlcusive to that addon.

To use them, at the top of each file add

local addonName, addonTable = ...

the names can be anything you like.

You can create a function

function addonTable:GetMapNameByID() 
    ...
end

Anywhere within your addon .lua files you can now call:

addonTable:GetMapNameByID()