Go to your game folder ( Like a million times before: Right click on your game in steam library -> Manage -> Browse local files ) and open the folder ScummVM.

This will be our GameRoot Folder from now on ( GRF from now on ).

---

If you want voices and subtitles in different languages... this is the perfect time to do it.

First set your game on steam to download the language you want for the subtitles [ You can do it by going to your Steam Library -> Right click the game -> Properties -> General Tab ( Left Panel ) -> Language ] - I normally verify game cache at this point just to be clear ( In properties -> Installed Files Tab -> Click on Verify integrity of game files ).

Now, at your GRF, open monkey3 folder and then open RESOURCE. There you will find a file called LANGUAGE.TAB - Save it for later, since this contains Subtitles - I will just post official sites, sorry if you hoped for a Drive or Mega download :D - you can either rename it to whatever you want ( keep in mind that you will set it name back to original later ) or just Copy-Paste it somewhere else.

Repeat the process to change the language again so you get the voice languages.

Once it finish downloading, go to your GRF, open monkey3 and RESOURCE folder again, and overwrite this LANGUAGE.TAB file with the one we saved before ( Either by deleting it and renaming the old one, or just cut-paste back ).

As for a finishing touch, you will need to edit monkey3.ini file at GRF.

Search for language= and set its value to your subtitles language.
This is a list of supported Languages by Steam:

Note : You can also set ScummVM language by changing guioptions=sndNoMIDI noAspect lang_ to match your liking ( Downloadable values from Steam are : English, German, French, Italian, Spanish ).

Example:
For English:
For Spanish:

And you are done. Now you have Monkey Island 3 with subtitles you want.

Download ScummVM latest binary version ( Link here[www.scummvm.org] ) for your OS - If non apply, check if you can compile it[wiki.scummvm.org].

---

If anyone wants to contribute by doing and explanation ( text and/or video ) about compiling it... this will be your space.

---

Again, go to your GRF and delete all files ( FILES, not folders ) inside, except from the ones called migration ( if you have any - Windows users will know ) and monkey3.ini.

Now, extract ScummVM binaries to GRF. Once finish, edit ScummVM executable name to scummvm.exe.

Edit monkey3.ini, search for versioninfo= and change its value for current extracted ScummVM version ( As for today that would be 2.8.1

And you are done.

There are a few thing you can do now that you have all set up and running.
Load the game - No need for difficulty to be selected and press Control+F5 ( Windows - Sorry Mac players, need to do some research ) to open ScummVM menu and select Return to Launcher now you can set:

• Global Options...
  
  • In Graphics Tab : Select Aspect Ratio Correction, Fullscreen mode, Filter graphics ( Juicy stuff ) and V-Sync.
    Also you can Download Shaders - Worth trying.
    
  • In Audio Tab : Select output device and global setting for speech and subtitles ( I set both here )
    
  • In Volume Tab : Self explanatory.
    
  • In Misc Tab : You can enable Discord integration, and enable auto updates.
    
  • In GUI Tab : You can
    
    • Change GUI Theme ( Default is ok... It won't hurt your eyes ).
      
    • Change GUI Lang.
      
    • Disable fixed font scaling.
      
    • Download Icons.
• Game Options... <- Juicy stuff
  
  • In Game Tab :
    
    • Enable the "A Pirate I was meant to be" song - Was it disabled by default?
      
    • Fix Original Bugs.
      
    • Audio-Visual Improvements
      
    • Restored content
      
    • Modern UI/UX Adjustments
  • In Graphics Tab :
    
    • Select Override global graphic settings and click on Shader:.
      There, on the search bar, type xbrz and choose the one with freescale ( Either with or without multipass, your choice ).
      
    • Once again mark Fullscreen, Filter Graphics and V-Sync.

Game without Graphic Settings:

Game with Graphic Settings:

( Yes, my screenshots are in spanish, yet I didn't translate this guide - yet - :D )

If you already have a ScummVM installation ( because you love old games and have it somewhere else installed ), you can theoretically use that installation.

Whenever I have the time, I'll tell you all how ( Or you can leave it in comments :D - I'll add it to the guide and add you as contributor )