Help! Current version of theme is broken

I downloaded Customizr 3.4.6 today, and found that my front-end pages were blank.

I deleted the them and tried to re-install it. WordPress is indicating that the theme doesn’t have a style.css file, and won’t download the theme.

I unfortunately didn’t make a back-up of the previous theme, so my site has reverted to Twenty Fifteen.

Is there something I can do, or is the theme truly broken, like WP says?