The number describes the red, green, and blue content in hexadecimal. If the previous sentence seems confusing to you, it is advisable that you avoid using this feature. A list of fonts is available for you to select from. Most fonts support the use of the transparent background feature. However, a counter with this feature enabled may not work well in all situations.
Some experimentation is required.
When a counter is first created, it starts off at the number one. But once a counter has been displayed for the first time, the starting number cannot be altered. The value of an existing counter cannot be altered. Feel free to experiment with them. However, all of the options listed may not necessarily be supported.