I would like to ask you Sandy ... Do you use the green pigment ink quite extensively when you make digital negatives? Would you recommend that an Epson 2200 owner start from the beginning by using the green ink? Should a beginner attempt to cultivate curves to match the printing process with the green ink for the type of negative desired? (i.e. pt/pd, kallitype, cyanotype)
I don't use the green pigment ink at all in making digital negatives. With the Epson printers that use pigmented ink you can get plenty of density on Pictorico using the black ink. The green ink is for use with printers that use "dye ink", not "pigmented inks."
In the long run you will get the best results if you develop a curve that is specific to your printer and printing process. However, there are generic curves available for the Epson 2200 for a number of processes and I would recommend that you start with them. I believe you can download curves for several processes, including Pt/Pd, from Burkholder's web site. I have an excellent palladium curve for the Epson 2000P but this printer does not use the same pigmented ink set as your printer and I am not sure how well it would work. But I will be happy to send it to anyone who might like to try it. But this curve definitely would not work with dye printers.