I am creating a theme for our reports and we use the OkViz Card with States visual.
I can format default features such as Title and Background for this custom visual using the guid:
PBI_CV_7B952816_A48F_49B4_9E13_15E3BB2C0337
...however I am unable to format custom properties. I've tried converting the .pbiviz file to .zip and reading through the .json file (which is where I got the guid) to find property names but they don't seem to override the default styles.
For example, the object has a property "dataLabel" which corresponds to the "Data label" in Desktop. The JSON file lists out the displayName and value contents but when setting these in the theme file it doesn't seem to work.
Anyone have luck with this type of theme formatting for custom visuals?