i have a big problem with gerber creation because PSD 14.2 create composite layers with negative plots and my pcb manufacturer can't use this type of gerber, he need a positive only gerber files.
Hello,
sorry, but i dont know how to convert layers between these formats. but if your problem is that you have inverted layers, you can invert they again an get the normal view.
I have used viewmate from pentalogic (a free gerber viewer and editor).