Version 1.4.2 (76) on Mac OS X 10.6.8 and Version 1.3.22 (73) on Mac OS X 10.5.8 do not show missing glyphs as open boxes or such as xpdf, gv, or Adobe Reader, Apple Preview, and so on do.
The PDF display is done by PDFKit, we are not involved. This also means thta Preview does exactly the same, so if there is a difference there is a difference in the underlying PDF, or perhaps in your font cache. I can assure you. And I can confirm with your sample.
Apart from this, it's not necessarily a bug.
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Using a font without Latin punctuation and digits
The PDF display is done by PDFKit, we are not involved. This also means thta Preview does exactly the same, so if there is a difference there is a difference in the underlying PDF, or perhaps in your font cache. I can assure you. And I can confirm with your sample.
Apart from this, it's not necessarily a bug.