This is not related to installation. GP (one of the libraries actually) can't read one of the font files on your system, but that's ok, provided export works.
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This is not related to installation. GP (one of the libraries actually) can't read one of the font files on your system, but that's ok, provided export works.
I see the same error message everytime I start GanttProject on my Mac.
It's probably not related to installation - but it's disturbing nevertheless.
If this is not an important error message it's better to suppress it.
Exporting a png image worked.