Finger rigging not working properly - please help!

Hi there, I’ve been working on a rig for a minecraft animation (yes I am aware there are a lot out there) and for my rig in particular, I have included fingers.

The fingers work properly on one side of the rig, like so:
https://www.dropbox.com/s/42u0rgbi4fq3bs9/fingersok.PNG

But on the other side, the fingers seem to “float” away, like so:
https://www.dropbox.com/s/dbdiww2sxkwraao/fingersnotok.PNG

I am not sure what the problem is, as the armature for that side was created by duplicating and mirroring the bones from the working side. I have checked to see if there are any issues in weight and if a bone has control over something it shouldn’t, but I have not been able to find anything like that.

Also, as a minor problem, could someone please tell me why this happens to the rig when I bend a joint (arm or leg), and how I can fix it?
https://www.dropbox.com/s/c5spa5odtrcjv1q/armbendissue.PNG

I would very much appreciate the help.
Any additional comments on how I can make the rig better (especially in terms of the bending in the arms, legs and ankle/foot area) would be very much appreciated.
I have attached the .blend file as well, if that will be helpful (file has been updated where finger limit rotation has been changed)
https://www.dropbox.com/sh/dne9p0q0au1iq1y/AADdhDU2-04mVnJfy-nRW-ZWa

Extra details about the rig in it’s current state:

  • FK rigging for the arms
  • IK for the legs
  • Extra bones created in the feet for foot rolls to make more realistic walking
  • Smooth bends at the elbows and knees (still being worked on)
  • When viewed in edit mode (mesh or armature) the pieces are separated
  • Shape keys have been used on the fingers (a separate mesh) to create sharp bends
  • Some bones in the arms have custom shapes
  • The head is separate from the body, and there is no bone to control the head protruding from the armature

For the right hand fingers you need to change the Limit Rotation bone constraint values so they can bend the correct way

I apologise for having not yet put the photos in, I didn’t have the time to.

Also, I’ve changed the rotation already on the version I’m still working on.
I’m putting up the photos now.