Example of how to change the 'The following events do not require payment at this time…' text shown when events are set to not approved. Change 'Add your custom text here' to whatever you want the section to show.

example.php

<?php //Please do not include the opening PHP tag if you already have one 

function tw_ee_custom_pre_approval_msg( $original_text ) {
  return 'Add your custom text here';
}
add_filter('FHEE__EE_SPCO_Reg_Step_Payment_Options___events_requiring_pre_approval__events_requiring_pre_approval_msg','tw_ee_custom_pre_approval_msg');