HELP: Mesh Gaps & Bone Properties Can't say I'm too experienced with modelling or Blender in general but over the past week or two have been learning to rig a model, part of which has had some extensive edits through swapping out different body parts from other models.

I've now been left with a bit of a problem and I have absolutely no idea how to fix it so I would appreciate any help anyone can give.

The torso is displaying a lot of blue lines in the mesh, sharp edges I believe their called, and when I try to pose the model the torso forms gaps where the sharp edges are as if there not attached. Anyone know how to resolve this?



The other issue I have is with the bones. This model it basically a reference tool, a manikin for me to use in Clip Studio Pro. Problem is that some of the bones in the hand are showing up as selectable for posing/distorting the model once exported and yet these bones should not be used at all. The same bone layout exists in some official modelling files I've used for reference, and those do not appear selectable in CSP. Does anyone know how to completely disable these bones/make them unselectable?



PS.
As you may have noticed in the last set of images, the armature has these bones - Bone.001, Bone.002, Bone.003, and Bone.004. They do not appear to be anywhere in the rig and I cannot seem to delete them. Anyone got any ideas how I can remove these seemingly redundant bones?

Any help anyone can give would be greatly appreciated. Thank you! :)
With the sharp edges/splits, it looks like the problem is that you are using an edge split modifier, and it is above your armature modifier in the modifier stack. Try using the up/down arrow buttons in the top right corner of the modifier to move the edge split modifier below the armature modifier.

As for the hand bones, I don't know enough about the export process here (are you using fbx or some other format?), but the bones may exist on a different bone layer in the armature. You could try looking through each layer under the armature tab of the object properties (the tab with the symbol that looks like a little man) by clicking on layers to toggle their visibility. 

The other alternative is that the bones may have been hidden using ctrl-h or similar. You can unhide everything in a particular mode (armature edit mode in this case) by using alt-h.