Print factories require CMYK PDF but you should prepare your artwork in RGB and the conversion to CMYK should be done as the last step - usually done in InDesign or Acrobat (or by printing machine as Theresa said)
Hi, would you mind being more specific? RGB and HSB are color models, not exactly profiles. Fresco on Windows doesn't seem to have any mechanism to set color profiles (actually, I couldn't find any setting related to colour management at all). Does it assume sRGB? Is it managed at all?