With our Xerox Colour C60 we tried to print on App Factory Expert White 188 micron/250 grams Polyester Gloss / Matt film. We experienced blanc dots, light glows and a light curve shape in full color photo's and on black shapes. We see this on both sides of the film.
We used the settings Heavy 4, and Coated 3. Also we tried to print it single sided and directly double sided, all from Tray 5.
What can we do to improve the printing quality on the films?
Consult the RML and follow the settings for whatever stock is nearest the specs of yours.