Hello all,
I finally discovered what happened.
When you create a partially tranparent element in artpro and set its transparency atributtes as "completely transparent" except for one concrete colour/s (i.e. 100% Pantone Warm Red , Transp. Cyan, Transp. Magenta, transp. Black, and 0% Pantone Reflex Blue), and export a pdf file, the result in Acrobat is that this object is detected as a DeviceN object, not transparent, because Acrobat understands that 0% of Pantone Reflex Blue is being used .that object. Therefore, an element filled in with two solid colours is a DeviceN.
I used Pitstop to see the element attributes with the inspector.
Can anyone confirm this info??
Buf!