It looks like the standard body mesh doesn't have a bone for the head. Have you rigged a helmet using that mesh?
I'll go through later today and try that and other methods again. This time I'll take thorough notes =p
The mesh does appear in the correct location, perched right on top of the head. It just doesn't articulate with the head. Oddly, when
the object had two meshes (a Fine Hat and the aforementioned static mesh), the hat would articulate properly and the other mesh would still trail behind. I'm really starting to think that it's some hidden aspect of the mesh itself that I can't find. I went through every line in nifscope comparing the file to a functioning hat, and the discrepancies that I found and altered didn't seem to make any difference.
One thing I did see in nifscope: under the NiTriShapeData, there are two lines labeled Consistency Flags. On the unaltered hat mesh the first is CT_MUTABLE and the second is CT_STATIC, with the first line being grayed out and un-editable. The flags on my mesh vary with attempt, but sometimes will have CT_STATIC on the first line, grayed out. Are you familiar with these flags, and could they be causing me trouble? Does the order of flags in nifscope actually matter?
Thanks for all your help.