Right...
Simply, the file acts as a piece of "unique" DLC, however, for the game to read this file, you need to be able to edit the "steam_api.ini" in your games folder.
WELL, as far as I know, this .ini does not exist in legit, Steam versions of the game. So you have to find a cracked version of this and the game's .exe.
I DON'T KNOW IF I'LL GET BANNED FOR THIS...But...Here's your cracked launcher. (Thing.rar) This doesn't include any DLC or anything, so I'm unsure if it goes against the rules...If so, banhammer in my forehead I guess.
Now using this WILL DESTROY YOUR SAVE FILE...But here's solution to *that*:
I lost my save file as well, but I was able to download a 100% complete save and use a re-signer to make it work for my game.
If you use the 3DMGAME.ini and the steam_api.dll, you will get a new save file under "1" folder. Drag it over the re-signer.exe to see what steam ID it is using and re-sign the 100% complete save file (or your old save file under "Documents\KoeiTecmo\DOA5LR\(userId)" folder) using that ID to make it work.
link to the save file re-signer and saves:
https://fileshare.steffenl.com/d/ecfdec45fe/
Credit to DiZpel on Steam discussion forums for the tool.
So once you're done with all that, download the nude mod on this post. This one has Lisa...But no Leifang. It's put together by Galhound of Lover's Lab. It should also work with ATI cards, so you don't get the barbie body problem. The hairstyles also work on this file as well.
NOW FOR THIS TO NOT CRASH YOUR GAME, you need:
-Aloha/Ninja 2015/Halloween Pre Order DLC
-Fun Theme Set
-Halloween Debut Set
-Tropical Paradise Set
-Variety Set
THE GAME WILL ALSO CRASH IF YOU'RE USING HOLDEN'S EXTRA BIKINIS MOD FROM LOVERS LAB! I believe he's working on a compatibility fix, but it will currently crash the game.
I don't exactly know how the Steam version works as I personally use a non-steam version, but if I've done everything correctly, all you should need to do is to extract the Launcher file into your games install directory, put the DLC file named "696969" in the "DLC" folder, and just run the game. I did add the proper line to the .ini, so you don't have to bother yourself with that. If I have somehow F'd up, you pretty much just have to add the line "DLC008=696969" to your newly downloaded 3DMGAME.ini.
OH, and in case, for WHATEVER reason, you become unable to change the settings of your game, there's also the fix for that. (I believe running the game from a cracked launcher can cause this.) Simply drop the files from the Fix into the game's folder, change your setting through startup_settings.bat and run the game from game.bat.
I hope this helps...SOMEONE, and if I get banned / this post removed for posting the cracked launcher...Oh well. I made sure it's only the required files and not anything extra to make sure it's technically not pirating, but...Yeah.