These are the tools that are being used by Starbreeze and LionGameLion for .model development with all the source that was possible to release to the public. Released with their permission as it has been greenlighted for modding usage. Involves all the source files which means you could also port them over to Blender (someday).

Special thanks goes to Ilija, Leon and myself on getting these out!

Requires Autodesk Maya 2011
The toolset is intended for Maya 2011 use.

Yes, you can use these tools to make:
-Characters,
-Animations,
-Sequence managers,
-Material config / unit / object files for your 3d models and write shaders for the game. You can also open units with the toolset as well.

Note: This is a resource made for mod developers with all the source files.
Yes, this will work for all Diesel Engine games released after 2011. PAYDAY: The Heist, PAYDAY 2 and RAID: World War II

As for installation: put it in documents/maya/2011-x64/scripts, it should look like this.

You will also need the version of Autodesk Maya 2011 64 needed for this to work, check the link down below and download the 64 bit version of the application.
https://knowledge.autodesk.com/support/maya/downloads/caas/downloads/content/autodesk-maya-2011-hotfix-3.html