... not sure but maybe the explanation is given in the log :
WARNING: TRenderManager::TriangleList_ProjectiveShadow()- internal buffer overflow.
[18:02:27] Too many vertexes or faces per shadow hier mesh!
In this example, you can see that in the shadow mesh (name starting with Sh) only the first 3 digits have been kept per line, from the original without shadow file ...
[Common]
NumBones 0
FramesType Single
NumFrames 1
[LOD]
1000
[Materials]
Gloss1D0o
[FaceGroups]
72 140
0 0 72 0 140 0
[Vertices_Frame0]
8.048001 -2.955997 0.324 9.955538E-05 -0.0001920014 0.0004480031
8.064001 -2.955997 0.304 0.0008064002 -7.679907E-05 -8.95935E-05
8.060001 -2.955997 0.316 0.0008960009 -2.800092E-05 0.0005599861
[Common]
NumBones 0
FramesType Single
NumFrames 1
[LOD]
1000
[Materials]
Gloss1D0o
[FaceGroups]
72 140
0 0 72 0 140 0
[ShVertices_Frame0]
8.048001 -2.955997 0.324
8.064001 -2.955997 0.304
8.060001 -2.955997 0.316
... you can check this easily by opening several D0 mesh files ...
If you can see that there are 6 digits, instead of only 3, in several [ShVertices_Frame0] files, then they need to be trimmed down to 3 digits per line, and you need MeshViewer to do it, otherwise it will be very time consuming and boring ...