Hey sp00kle,
Roland does not support this conversion because the ink system is permanently stained with white and metallic inks. So if you move to light cyan and light magenta, you're not going to get those colors. Light cyan will be contaminated with white and light magenta will be contaminated with metallic, so the print results will be less desirable.
If you have additional questions or need extra support directly from Roland corporate support, please submit an "official" support request form online here:
Product Support Form | Roland
If you do write us, we look forward to helping you and take care,
Roland Technical Support
Roland DGA Corp.
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