gearbox, LSD, clutch problems (56k)

[BomB191]

i pulled apart my spare gearbox today and found a few things i dont think i like there is a lot of play

and i found this just sitting in there

i wouldnt have a clue what it has come off.

allso looking at my LSD (if it is that i has a few chips in it)
is this a open diff or lsd?

did i split the gearbox in the right spot? cuz i cnt seem to get it back togeather?
also a *spare* ballbearing fell out when i pulled it apart but i cannot get to the far end of the box because it glued shut :S

here is the other side of the gearbox if needed...

any help would be a huge help

 

[fastglanza]

looks like a normal differential...and that thing is a magnet it has a compartment where it is slipped into