0. Find why only first frame of animation gets displayed.
1. Flexible clothing/customization system
1.1 Clothing slot system without node tree.
1.2 Character display without node tree. (?)
1.3 Character body morph system with bones AND shapes
    and pipeline for blend shapes; layered clothing optimizations.
1.4 Separate physical skirt rig(s) with automatic updates
(needed for long dresses)
1.5 3 rig system for character animation with physics.
2. Port LOD system from 4.x
3. Port AnimationTree expressions from 4.x
4. Port animation retarget system from 4.x