Importing mesh is powered by Assimp. Assimp support many mesh format, nevertheless we recommend .fbx or .obj.
Just set Importer name to OpenAssetImporter and Processor name to ModelProcessor, like below.
<Item Include="\Models\Tank\Tank.fbx">
<Name>Tank</Name>
<BuildAction>Compile</BuildAction>
<Importer Name="OpenAssetImporter" />
<Processor Name="ModelProcessor">
<TextureFormat>Compressed</TextureFormat>
</Processor>
</Item>
Just set Importer name to OpenAssetImporter, Processor name to SkinnedModelProcessor, and StockEffect value to SkinnedEffect, like below.
<Item Include="\Models\Karakter\Karakter.fbx">
<Name>Karakter</Name>
<BuildAction>Compile</BuildAction>
<Importer Name="OpenAssetImporter" />
<Processor Name="SkinnedModelProcessor">
<StockEffect>SkinnedEffect</StockEffect>
<TextureFormat>Compressed</TextureFormat>
</Processor>
</Item>
Defaultly, TextureFormat is Compressed for best performance when rendering. You can create custom Importer library .dll to support other mesh format.