Solution: The user Conn found the following fix, quoted here from his original post. Find the file font-win.prf, and change the values indicated to those he lists below:
I have found a solution. <br> <br>In Lib\user\font-win.prf edit this: <br> <br># Floors (white / centered dot) <br> <br>F:1:8/46 <br> <br># Invis traps (white / centered dot) <br> <br>F:8:8/46 <br> <br> <br>This should correct the problems with walls not being displayed correctly, and a bug with disappearing torch light around the character.


