I have a design that was converted from and earlier version of PCB Editor (16.0) to version 16.6 PCB Editor. After the conversion the padstack definitions have the top and bottom layers swapped.For example, it I define a square pad in the padstack definition on the Top layer, the square pad will show up on the bottom layer and vice versa.
According to the cross section manager the layers labeled Top and Bottom are in the appropriate place in the board stack.
I created an a new padstack using the external tool and replaced the padstack definition in my design. The result is the same, the top and bottom pads are swapped. I have not tested to determine if the internal layers are swapped in any way. This inner board layer definitions are all the same for my padstacks, so it doesn't make a difference based on the current design.
Any help would be much appreciated.