I just changed from the plugin "Google XML Sitemap for Images" to yours. But when I created a new sitemap it kept showing the one generated with "Google XML Sitemap for Images" and not the one created with your plugin.
So I went in and deleted the sitemap manually from the root directory. Now when I generate a sitemap (with your plugin), it does not generate a new sitemap.
I hope you can help me!
All the best