How to change color of sketch in an Assembly Document using the API

Hi,  I have a question that I couldn't find an answer to after days of searching.

We have an assembly document that has several sketches. It is important to distinguish these sketched by coloring them. In the GUI, this can be easily done either through the Sketch/Curve Color functionality or using the Line Format toolbar. What is the corresponding API to get the same functionality (something that works with C#)?

When you record a macro of the Sketch/Curve Color functions, nothing is recorded. When you record a macro of the Line Format functions, they appear but the functions used (SetLineStyle, SetLineWidth, SetLineColor) are only defined in PartDoc or DrawingDoc. Running back the macro produces a run-time error 438 "object doesn't support this property or method".

Any help is greatly appreciated!!

SolidworksApi macros