a working title for a font I'm working on is "47HalfTon".
In every application it's be tested in the name shows up as listed above.
In InDesign, it is "74HalfTon".
AFAIK, the restriction that font names must begin with an alphabetic character only holds true for the PostScript Name.
Since there are various different name fields within a font, I suspect that you may have mistyped the name in one of those fields and that InDesign is getting the name from that field whereas other applications are getting the name from somewhere else. In FontLab, double check that the name used in the Font Names, OpenType-Specific Names, and Additional OpenType Names all contain 47 rather than 74 and that your PostScript Name is something like 'FortySevenHalfTon'.
André
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