Thou shalt not use PHP variables of any kind inside a translation function’s strings.

Even text domain strings need to stay hardcoded as actual quoted strings, according to http://markjaquith.wordpress.com/2011/10/06/translating-wordpress-plugins-and-themes-dont-get-clever/ but not changing it as yet
Removes variables from translation function's strings. Fixes a register_taxonomy argument, should be show_admin_column instead of show_column
Removes the CUZTOM_TEXTDOMAIN constant in favor of using actual (single) quoted string 'cuztom'
Removes cuztom text domain from 'Date'

WordPress already 'Date' already.