@hiccup Is there any code for the shapes?
They need to be 16x16 px, preferably using transparency.
For bitmapped skins you place these image files into the 'Images' folder.
For regular skins you will need to encode the image files to base64 and copy that code into the main skin xml.
What is meant by "Uses shape and color" is that for most instances, the 'love' icon will appear exactly as the png, but in some positions only the shape is used, and the colour is overruled by an rgb value in the main skin xml.