Is it possible to use a SVG file with multiple paths like it is one path? So one changeble color for all paths?
Yes, if you use this option:
You can switch between there being a selector for individual paths or one for each colour.
I mean when a customer adds an image from the fancy designs, at that point he can change all the colors for every path. So i am looking for a main setting here
Sorry, there is currently no setting for that. You could head on over to the feature request forum and submit a new idea for this there.
Is there a universal setting for Colorpicker for every path option?
Just thinking about when I set up a blank product and want the customer to choose from different options