I will look for another Simplified Chinese font (definitely TTF) and try with that.
Regarding large font size ... if you try DejaVuSans-Bold you will see that you can't generate a size >150 ... mcufont just exits (with no error reported).
Also, if you do manage to generate a large font ... e.g. Anton-Regular at size=182 (the largest that produces a DAT file) you will find that the gU8 font->line_height field is "267, /* line height */", which isn't working well because the field was too small!
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