I do my fonts like this
Code:
// Text setup
#ifdef OS_OSX
static char* fontName = "SomeFont";
static IText::EQuality texttype = IText::kQualityAntiAliased;
static int lf = 11;
#else
static char* fontName = "SomeFont";
static IText::EQuality texttype = IText::EQuality::kQualityClearType;
static int lf = 12;
#endif
static IText lFont(lf, &COLOR_BLACK, fontName, IText::kStyleNormal, IText::kAlignCenter, 0, texttype);
It is not the most elegant, but it works. Normally one size smaller for OS X is pretty close to the same.
Also, make sure that the font is installed on the Windows and OS X computer. This sounds obvious, but a default font will be substituted if the named font isn't found.