There is no switch or options to check for embedding fonts in .ps forms.
The way it works is host-based fonts, such as TrueType fonts or PostScript fonts that you've installed in PlanetPress, will automatically be embedded in the .ps file. However, printer-based fonts, such as the ones you can choose in your styles under "PS, Printer, single-byte", will NOT be embedded in the .ps, as they are printer-resident and cannot even be accessed at the compilation time. This means that if you use printer-based fonts, you must make sure that the printer has the font, otherwise, it will not be able to use that font.
Hope that helps!
RaphaŽl Lalonde Lefebvre