My question is from a mod distribution point of view.
Is there a specific packing type tool to package mods, and then users just have an easy way to install a mod. Or is it a case of supplying something like a compressed file and giving end users instructions to copy files to the CUSTOM folder?
Would a mod that is different to a core function of Reunion such as the menu changes, be something that is possible to do with this modding framework?
It'd probably be more accurate to say that there isn't an install process:
Download a zipped folder that the modder has prepared.
Unzip that folder and put it into Reunion's Custom folder.
Open Reunion's .txt and type in the mod folder's name under the Custom heading.
Manual, but very straightforward and should take 2-3mins total.
As for menu changes, R06 has hext and can read texture, etc. files so I'm assuming an alternative menu mod can be applied to it provided the one it comes with is disabled.