New bug, can someone please check and confirm - Subtract operation fails and deletes original. Hi AllHi

Hi All,

Can someone please load and check this on another PC? It's a copy of Aerospacedesk's file that I was playing with, and noticed something funny post-subtract, with what appeared to be incorrect function when a 2D shape was merged with a 3D shape - so I attempted to perform a subtract operation to confirm and the result was the typical "delete the original" failure when an operation bug is identified.

To check, please subtract the red box from the yellow object - 

Expected result: A square should be cut out of the 2D seeming disk that wasn't removed by the prior operation.

Result: The original model and the subtract model are both deleted.

BUG DISCOVERED 7266.Alclad Base Fillet Exercise 10042015 (1).dwg

Thanks

David