That error appeared because particular mesh doesn't have any actual data within. Viewer works with such meshes, but export crashes because currently only lods count is checked in export functions - so if you have a mesh with 1 lod, but 0 indices/vertices, you'll get a crash upon export. It's not the only game with such issue, if I remember correctly. Here is sample package for future references (
link).
@Abchihba: You can use specific build from
this topic in the same way as official build, that issue is solved there.
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