The problem is the same one that keeps cropping up, i.e. - me.
Running it again on a fresh test page (with recordset rs_test) with your first code:
<?php echo(date("d/m/Y", $row_rs_test['time_last_run'])); ?>
Returns the date just fine. I now need to back-track and see how I messed up the first time.
I think it is my destiny to make others feel better about themselves and their abilities by displaying my ignorance on these pages. Thanks for helping out - sorry to have wasted your time again,