Missing image ui-bg_flat_75_ffffff_40x100.png

Thank you for the plugin, it is very helpful. the issue we are having is the 404 error when trying to access https://www.uapi.us/resources/plugins/tag-groups/css/images/ui-bg_flat_75_ffffff_40x100.png, either the css which calls the file is mis-configured or does not exist on our server. You can see the error occurring at https://www.uapi.us

If it makes a different, our Tag Group theme is set to ui-gray

Thank you for any information you can provide on how to get rid of this error.

Louis

https://wordpress.org/plugins/tag-groups/