Something like Config.lua -- Most global variables and file local variables would be set with e.g.:

KillingBlow.lua:
local pvpKillsOnly = AUDIO_Qs.SetVar("PVP_KILLS_ONLY", true)

Config.lua:
local editConfig = {
["PVP_KILLS_ONLY"] = false,
["DEBUG"] = true
}

AUDIO_Qs.SetVar(valName, val) {
return editConfig[valName] or val
}

This file would be edited only in the retail/interface/addons/audioqs/ folder of a testing install, the "dev" Config.lua would be swapped out for the "live" Config.lua for final tests, then zipped for live distribution.