I guess you mean you use command "volume unroll" and you want to the new volume it creates to have the same colors as the original volume surface.  I don't think there is a way to do that.  The command produces a new unrolled volume and then computes a surface of that new volume.  That new surface has different numbers of vertices and triangles and cannot be matched to the original unrolled surface.   So you would have to reproduce a similar coloring on the new volume.  For instance if you did a cylindrical radial coloring on the original helical volume you could do a height based coloring on the unrolled flattened volume to get a similar coloring.  If you were using color zone coloring to transfer colors of atomic structures to the helical map you might have to try to fit those atomic structures to the flattened map and do a color zone.  If there were a way to unroll the surface that produced a new surface with the same triangles and vertices only flattened then the colors could be preserved, but ChimeraX has no ability to unroll a surface.

Tom