[Quote]Why are some models compiled while others are not?
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This is due largely in part to the apparent limitations of nwncompDcomp's ability to properly process models with skins or complex animations. During testing it was discovered that several models, when compiled, displayed various issues ranging from broken animations to causing the Toolset to crash.
It was decided to leave some models in their decompiled states and let the Aurora Engine compile them as needed. The increase in load time was found to be negligible.