I think the scaling problem could have been fixed within the character menu>then bone tools>under object properties> reset scale. Then as usual, reset the pivot point of the mesh to origin or model center and apply a reset xform.
You might encounter some problems down the road caused by the way you created your bone rig. If you successfully compile the model and see messed up animations on one side, it will be a pivot point problem caused by mirrored bones.
Bone pivot changes depending on which viewport they were created in. You probably need to change the reference coordinate system to "world" instead of "view" to make it the same whatever the viewport you work in.
I used to be in touch with a modder that started working on IK rigs, but i have no idea how it turned out but here's my thoughts on this...
I'm not sure IK solvers is a good idea, the GLA. stores the actual bone rotation to animate (like key frames in max) if key frames are written for all bones when animating with IK then it should be fine, if not, then the compiler won't have all the information it needs to replicate the actual animation sequence, so only the parent bone would deform instead of the whole chain.
Maybe it's just me, but i like keeping things simple when learning new stuff...once i have a working prototype i experiment