"bone indices and weights are four dimensional data. Bone indices and weights should use the byte data type while all other vertex arrays should use the float32 data type"
looking into the sample models in the asset pack, it seems that the vertex arrays for these are actually using int32 and float32 data type rather than 'byte', so if you are making any tools etc. double check this for yourself (I am an exporter writing noob so I may have misunderstood something as well..)
If any devs come on here and are willing to chip in with sme info it would be cool!
