The same block is shown in many ways… none of them right. Show fills on.
Please post your sample file so I can try and see what is going wrong
In the file above it was just a blocked box copied several times. Now I was trying to do the same thing and i run into something else:
The fill surface is not visible for selected instances.
So my steps are quite basic: Open Rhino, draw box, block it, create a clipping plane to cut it, copy the block a few times.
Since these display problems are so obvious I suspect them to be related to my graphic card.
I attached the file but I doubt that you will run into the same behavior.