Select Theme For Theme Page not work on my multisite!!

I followed the following intruciones but nothing happens!

Choose the theme that you want to use to display your theme page. You can add your own themes into "wp-content/uploads/multisite-theme-manager/your-theme/" folder. (Tip: duplicate the default theme from "wp-content/plugins/multisite-theme-manager/multisite-theme-manager-files/themes/" to get started.)

the selector box always stays in 3-Eight!!