Could you maybe make an video on youtube to show how to apply the translation or maybe share a URL were its shown. Of course if its not asked to much
I made you some pictures to better visualize the steps (click on the thumbnails to make them larger):
Before you can apply the MTL you need to extract and then move or delete the "Game.rgss3a".
You can do this using the rpgmaker "All Decrypter".
Just run the "RPG Maker Decrypter.exe" and choose the "Game.rgss3a".
Then move the newly created folders from the "Extract" folder to your game folder
After that move or delete the "Game.rgss3a".
Finally merge my MTL into it (Just drag and drop everything from the zip into your game folder)