Problem with black squares

I wanted to cover a custom map in black squares so my players can uncover an underground crypt by their own and i will delete the black squares when they uncover a room. The problem is now after setting all black squares i can't interact anymore with the lower part of the map. If i click on the black square on the lower half of the map it will just select the map. Edit: it seems the system automatically group the black squares with the map while i never gave the command and doing ungroup does nothing.

Hi Willy! Without actually putting hands in the game, it's difficult to say what exactly is going on. However, is there a reason you needed to go this route instead of using the built-in Fog of War feature?

Hi Willy,  I suspect this has to do with a recent bug where art objects are inadvertently treated as grouped together.  As Keith says, I suggest using Fog of War instead.

thanks all, the fog of war feature is gold!