Exporting models and animations from the game for use in Unreal Engine.

After trying to import these same 2 files into 3ds Max 2018 and 2020, all parts of the mesh started moving correctly, but there was a problem where the mesh began to "tear" in some places. I noticed a similar problem with other models in these versions of 3ds Max; this looks like a bug in the SMD plugin.

I've noticed similar defects. It might help to select all vertices after loading the SMD file and press Break, then select the vertices again and press Weld Vertices with a value of 0.001 (demonstrated in the video).
I also noticed black normals on the models. They can be fixed by unchecking "Rebuild smoothing normals" when loading the SMD file and then manually assigning smoothing to the polygons (demonstrated in the video).
The SMD plugin from Wonderboy causes some defects, so I used the plugin from NeilJed.