I have downloaded the classic movies mod for BG:EE but partway through the installation it fails stating that permission to access the baldur's gate ini was denied. My understanding is that the current versions of BGEE have no ini files anymore (if they do I can't find it in the game folder or in documents). Does anyone know how I could resolve this please?

There is a Baldur.lua file in [User Name]\Documents\Baldur's Gate - Enhanced Edition\ which is modified by the mod.

You can try running the setup as administrator. Also check the Baldur.lua file and make sure you have permission to edit it (Right click > Properties > Security).