Image? As in a bitmap?

If so, there's nothing to really do as everything inside Xara products are really RGB. If vector elements are colored using CMYK, all it takes is exporting to PNG, they are now RGB colors. Or, if exporting to PDF, make sure you are not using any of the PDF/X types of PDFs and check in the export dialog to make sure CMYK is not chosen for the color model (usually isn't).

Beyond that advice, I would need more info about what you are creating and for what purpose.

Mike