Putting the Flag Together

Have made it 1/2(?) way through the knight. I have all the pieces of the flag. According to the map there are no more active areas. I have explored and poked every possible area. The walk through (not posted here!?) says that I need to go into the hall outside of the cell, click on the wall and put the flag together. Except, it isn't letting me click anywhere in that hall. There is a magnifying glass cursor over the far door with a sun(?) on it, but no words or dialogue pop up, nor can I put the pieces of the flag on that either. I also tried putting the pieces of the flag directly on the flag pole.

I restarted, and reinstalled...no difference.

Am I doing something wrong, or is this a tech issue?

Make sure you are "outside the CELL". Good luck!