2.2 Using MultiAssist and editing your new animation file
With the Extract tab selected, we first select our .pap and .sklb files. You can select these with the in-app file explorer by pressing [...] or by typing in a path manually.
With the paths to the respective files set, press [Submit] to populate the animations list in the lower left corner. If your .pap only has one animation in it, only a single animation will be displayed here, otherwise, select the animation you wish to extract. If you change the .pap file at any point, make sure to press [Submit] once again.
The export options in the lower right corner allow you to select the file type and path of your exported animation file. I'll select .fbx and name my animation file export. Select your export directory and press [Export] to begin exporting the file. This should be a very quick process.
Please make sure you have everything correctly inputted before pressing [Export]. If successful, there will be a success dialog displaying the export directory.
ISSUE WITH FBX SUPPORT IN v0.2.0:
Please either use Blender to edit your FBX files or first import/export your FBX file from Blender before using another editor.
The exported file can be imported into your 3D editor of choice. If you are using 3DS max you should see Animation Take: Havok Frames when importing. The default import settings should be correct for 3DS Max. In Blender, you'll likely want to set Transform: Scale to 100.0.
Make as many edits to your animations as you'd like, and export the file as an FBX once again. Make sure Bake Animation is selected, and if you have multiple objects in your scene, make sure to only export the animated armature.
With the edited FBX, we can proceed to repacking the file.
From the AnimAssist README.md
Open 3DS Max and check the Plug-in Manager to ensure HavokMax is properly installed.
From the Max menu, click Import and select your output_file.hkx from the previous step to open it in 3DS Max. Select disable scale, invert top, and set Back: Top. Click import, and you'll get a wonderful fistbumping skeleton, read directly from what was once game files.
You have some sweet changes to some animation, but now we need to put it back into the game.
From the Max menu, click Export and type any filename you want, and save it in a cool, dry place. In the "Save as type" drop-down, select "Havok Export (*.HKA, *.HKX, *.,HKT)". We will be saving an hkx file once more. Export your file, again, selecting disable scale, invert top, and set Back: Top. You must select those, as well as Export animation and include skeleton. Set toolset to 2014. In my testing, I found that it was optional, however, it seems safest to disable optimize tracks according to user reports.
Additionally, make sure the Start and End is set to the correct frame range.
Your settings should look like this:
Not properly implemented yet. The XML file will contain all animations if more than one is present. These probably aren't super useful. Both files (and the .hkx packfile) can be opened in Havok Standalone Tools, but probably not much else. I consider the xml file useful for debugging. At the current time, these two formats cannot be repacked into a .pap with MultiAssist.