The Doom menu has a huge problem: many settings like difficulty or Doom style doors are unchangeable via the menu and they spawn console errors everytime I try changing it, so I have to change them through the console.
This is the error which console sends:

[ERROR] addons/gmdoom_133300986/lua/doom/convars.lua:29: attempt to call field 'CvarSet' (a nil value)
1. unknown - addons/gmdoom_133300986/lua/doom/convars.lua:29
2. unknown - lua/includes/modules/concommand.lua:54