How to preview geometry in Dynamo for Revit inside a custom node

Question

this is for anyone familiar with Revit, Dynamo, or C#.

I'm trying to create a custom zero-touch node using C# that will highlight a chosen curve as colored geometry in the preview window, while remaining inside of a loop.

So far I can only preview geometry by returning it, and I can't apply a color to the geometry without using the Display.ByGeometry node on the canvas.

Here is the most sensible attempt at this I have so far, and it still doesn't work. The code runs without errors, but I also don't perceive any change on the display.

public static void ColorTest (Curve crv)
    {
        Cone cylinder = Cone.ByPointsRadii(crv.StartPoint, crv.EndPoint, 1, 1);
        DSCore.Color red = DSCore.Color.ByARGB(255, 255, 0, 0);
        for (int i = 0; i < 1000; i++)
        {
            Display.Display.ByGeometryColor(cylinder, red);
        }
        temp.Dispose();
    }

Any ideas would be much appreciated.