If you have an order with a simple kit item that contains several items and you change the quantity to ship on the main kit item number, the kit item quantities get messed up.
 
1. Enter a kit item with a ship quantity of 2 and a Backordered qty of 0.
2. All the kits items get copied into the order.
3. Go back to the kit item line.
4. Change the ship qty to 1 and put 1 in the back order quantity.
5. Answer Y to the questions to change the kit items proportionately.
6. The kit items get changed to:
     Origonal Order Qty = 1   (bad, should not have changed from 2)
     Qty Ship = 1                  (good, kit item was changed from 2 to 1)
     Qty Backorder = 0         (bad, should be 1 because kit item was changed to 1)
 
It looks like when it "automaticaly adjusts" the kit items, it is changing the origonal order qty to a 1 instead of changing the Qty Backordered to a 1.  This overwrites the 2 that was origonally in the "origonal qty" field, and does not update the Qty Backordered field.
 
 

I haven't noticed it in our everyday operations, as it's not a situation we would normally have. However, I did confirm in our Test Company that we do have the same behavior. Sorry I didn't reply sooner, I assumed that IST would confirm.