It seems that we need to use this modifier on the armature inside Armory. If we don’t apply it on the mesh of the armature, we get errors like uncaught exception on " var refs = this.data.geom.skeletonBoneRefs".
Then if we apply it on Armature with object Relations>Parent>Bone, this modifier creates wrong/strange deformations during the Play, using Nodes or Haxe.
Is it a well known bug? do you have any idea what caused this problem?
Therafter a kind of checklist that could help :
1/ added the Modify Armature on one of your Mesh with Bone Envelopes option checked (my omission)
2/ at least one animation in place, such as a rest state.
3/ all the orientations of the bones and meshs must be perfectly controlled