Theme Check Warnings

Hi, I ran Theme Check Version 20150818.1 | By Pross, Otto42 and saw these warnings: REQUIRED:.screen-reader-text css class is needed in your theme css. See See: the Codex for an example implementation. WARNING: Found a translation function that is missing a text-domain. Function esc_attr_e, with the arguments 'Click Here To Edit' RECOMMENDED: Screenshot size should be 880x660, to account for HiDPI displays. Any 4:3 image size is acceptable, but 1200x900 is preferred. INFO: More than one text-domain is being used in this theme. This means the theme will not be compatible with WordPress.org language packs. The domains found are catcheverest,_s Is this something important? Thank you very much