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Don't worry, let's break it down!

1) For the RPG Maker MV content, just use the files you find in this folder: "5_RPG_Makers" -> "RPG_MAKER_MV"
2) Some of the features are disabled for the rpg makers due to the software limitations
3) There's a txt file in the above mentioned folder to help you import all the stuff
4) Each tileset is bound to a certain tileset slot or a certain group of tileset slots, here's a video of what each one does:

Good luck with this, you can do it! 
Comment again if you need further support ;)