The split version is just for ease of download if you have an unstable internet connection, but they aren't independent pieces of the game.
It's just the original archive split into five partial archives, but you still need to download them all to reconstruct the original archive.
You can't unpack a single part.
So, if you already have the full archive there's no point in downloading the split one, because at the end of the story you'll just have another copy of the game you already have.
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The compressed version, instead, has lighter images and animations, so it could be fastest to play on slower hardware... Provided that the glitch comes with rendering of pictures and animations.
If the glitches you are experiencing comes from the running of python scripts, then you'll notice no speed increase with the compressed version, because the scripts are exactly the same.