This guide assumes that your familiar with UndertaleModTool and GMLoader

Converting xdelta mods

• Rename the vanilla data.win into vanilla.win
• Put your data.win that has been patched using xdelta patcher into the game folder and rename it into modded.win
• Run GMLoader Convert.bat

After it has finished running you will have converted_output folder, rename it into mods and then you can load your mods using GMLoader. Don't forget to convert the code files into code configuration files to have the best mod compatibility.

Packaging mod files

A good practice to package the mod files is to package them as if they will work when the archive is extracted as is to the game folder.

mymod.zip
├── mods
│   ├── code
│   │   ├── mycode.gml
│   │   └── myothercode.gml
│   └── textures
│       ├── mytexture.png
│       └── myothertexture.png
└── lang
    └── english.txt