Merging plugins

[Herolegend]

hey there, I have a few questions about merging plugins and using masterfile so far iv been doing it with CS set, when i merge say 10-20 or so different weapons and armor CS asks me to set a plugin as master plugin, now i set any random mod as a master file but im curious what it does and do i have to set a master file? also if there is a better way of merging plugins with TES4Gecko and a lil guide how to do it if possible?

 

edit- I installed tes4gecko and think its pretty good, but i'm curious can i merge plugins that have already been merged? also can i take one plugin that was merged that for instance a mod gets updated, could I replace the plugin inside the merged file with the updated esp version?

 

eg/

Merged 15 mods .esp one of the mods called longtop unfortunately giving me black screen when i wear it, so thinking about downloading the updated version to install over it, but how its already merged into the merged 15 mods.esp?

also a way of taking out a single plugin thats been merged that i no longer want in game?