1. No matter which repack you downloaded you have to update it to latest version from official source otherwise there may be incompatibilies with newest plugins.
For JAP version use
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For international version use
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It's your responsibility to know which version of the game you have. You can't install Eng update on Jap version or vice versa or you will break the game.
2. It is necessary if you want all 22 personalities. You don't even need to touch CM if you don't want to. You just link it to COM and let it sit there. Linking COM to CM will give you access to CM costumes and personalities and will provide much better mod compatibility. If a mod requires CM assets it will throw errors otherwise. The modpack in op is an amalgam of CM and COM mods. There are workarounds if you really don't want to install CM.
3. Mods will work fine. Plugins, I don't know. I don't own a vr headset. I think that plugins ui don't display well in vr and you might need to install something else outside of the base CMI config. Your best bet is to join
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and ask there what you need to make the vr experience better.
4. You are comparing apples with oranges really. DV was just one retired modder. CM discord sometimes tries to gather lost mods from retired modders and reconstuct their deleted repositories. By definition they are both modpacks. However one is designed as an addon for the game that bundles many various mods from numerous modders. Mods that are tested and guaranteed to not cause issues if you follow some basic general instructions. It also includes complete character presets. The other is just a bunch of mods made by the same author.
My modpack is designed to include all the common parts required to reconstruct downloaded presets. A good chunk of them are nearly impossible to find nowadays because they were either deleted or locked so this is your only source.
5. It really depends on what you want from the game. If you are a collector, want all personalities, all the events and full mod support out of the box then you need jap version. Both CM and COM.
If you don't care about story then eng version will do just fine. I made a compatibility patch for the modpack to work with
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. Keep in mind that mods outside of the modpack may have other requirements for Jap COM or CM assets and will not work out of the box. They can be fixed to work but this requires some basic knowledge of how mods work.
So overall the jap version is better because you have native support for everything. On eng version even if the installation process looks easier, it takes less storage and load time is faster, you will eventually run into issues that require time consuming workarounds.