Could someone answer this for me?

Whenever I download the current MPCORB file and turn on the "Use
MPCORB" option under the Extras menu, I lose the display of all my
deep sky objects.

When I un-check (or turn off) the "Use MPCORB" option, they come back.

Even when I have the asteroid display turned off, the deep sky objects
disappear.

Why? Any ideas?

Thanks!
-Scott