Download the following image:
Place it on the background scaled to 0.557
Screen appearance should be:
Select the diamond, then select the "Curve Edit Mode" (third edit mode on the far right --- it may be necessary to select "Node Edit Mode" (the one in the middle) first):
Point to the top node, it should highlight black, then click, hold the mouse button down, and while holding, drag to the left or right (the necessary direction will depend on the order in which the nodes were clicked originally --- most drawing programs expect the same winding rule as PostScript, left-hand fill --- fill is towards the left-hand side of the path --- the diamond points should have been clicked in counter-clockwise order, and one should drag to the left) until one gets to the point in the background --- release the mouse to achieve:
Repeat this process until one has:
Targeting the nodes is a bit tricky, and I find the (occasional? bug?) need to click on Node Edit Mode first a bit odd. It may be on a high-resolution screen that the nodes are very small and difficult to target --- unfortunately, Carbide Create lacks an option for setting a number of pixels to relax this targeting, nor to afford the user control over the size at which such selected node highlights are drawn. If you have any difficulties with this, please contact firstname.lastname@example.org and we will see what can be done.