In the file saxon/inc/theme-dashboard/inc/theme-activation.php find the function main() which starts on line 22 and add this to the start of the function code:
if(get_option( 'saxon_license_key_status', false ) !== 'activated') { update_option('saxon_license_key_status', 'activated'); update_option('envato_purchase_code_saxon', '123123123123'); }
All done. Just install the plugins and then you can install the demos.