Symptom-first diagnostics

Isolation ladder

1. Play the source Animation Sequence on its intended source mesh.
2. Preview the IK Retargeter with all optional operations disabled.
3. Validate chain map and dedicated retarget pose.
4. Enable Pelvis, FK, Root, IK, pin/contact, and curve operations one at a time.
5. Export one sequence and play it directly on the target.
6. Test runtime Retarget Pose From Mesh without target overlays.
7. Re-enable the final AnimGraph from base pose outward.

The first failing rung owns the investigation.

Symptom	Inspect first	Then
Target frozen or stale	source mesh tick, source component, attached parent	graph order, LOD
Limbs explode/contort	chain start/end/map	retarget pose axes, FK rotation mode
Knees/elbows bend backward	pose bend direction	preferred angles, goal space
Floating or sinking	ground alignment, pelvis op	root height, floor constraint
Foot sliding	source speed vs target motion	Speed Planting curves/goals
Hand/weapon offset	arm/hand chains and pose	Pin Bones, goal offsets
Root motion absent	source root data and root op	export/root-motion settings, movement owner
Root motion doubled	duplicate translation owner	AnimBP/movement integration
Preview correct, export wrong	export root-lock mode	curves/bake settings
Preview correct, runtime wrong	component parent/source/tick	profile, LOD, node order
Works near camera only	animation/solver LOD	required bone stripping

Capture: source/target asset names, skeleton roots, retarget roots, chain map, retarget pose name, operation stack order, runtime component hierarchy, node order, and the shortest failing clip. Do not tune several offsets at once.