This was caused by character set incompatibility between message and map
windows. Apparently, Nethack is using IBM character set (CP 437) but fonts
were create for Windows ANSI codepage. I fixed most of it by changing
character set of the fonts except for the Rogue level. I had to make changes
to src/drawing.c for Rogue level since most of Windows fonts are not capable
of displaying control characters (char. code<0x20)
And of course, disabling IBMGraphics option fixes it all.
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