the colour that is supposed to be printed white has to be of the type "sport" (not just a named colour in e.g. cmyk mode)
then import the file in the caldera rip, drop in onto the driver
select your media
select resoloution: here you HAVE TO to select one that has "white" in it, for instance "720x1440-white+colors" - you need to create a profile first if you dont have one ready (some might be available for some media from the manufacturer, but for the specila inks printing usually not...)
then in the driver, click on the first "tool icon" (page setup), in the right half of the wiwndow there are several tabs, one of them is called "White"; here you need to activate the checkbox "Enable separation" at the top and select the option "use spot color" and from the list of the spot colours choose the one that is to be printed with white ink (if you have named it White the rip will select it automatically); lower in the wiwndoww select "Level 1" and make sure that the checkbox "Linearization" is UNckecked; click "close"
now - just to make sure - click on the second tool icon (wrench) to review and possibly modify printer specific setup; on the "Prinetr" tab for at least one layer "spot" or "White" must be selected; here it really depends on the job and i will not go into details here and now. when all is set click "close".
now you can print - of course before that you should make sure that the nozzles for white ink are not clogged...
