By adding 
	$event_params['userprops'] = $userprops; 
and a new array 
	$event_params['props2update'] = $props2update;
which is generated by
	$props2update[$propname] = $val;
in the loop right before
	$ret = $this->SetUserPropertyFull( $propname, $val, $uid );
to the $event_params array in "action.do_userchangesettings.php" you can show
the affected properties in the notification e-mail.

The following template only shows the values the user has changed:

*****TEMPLATE BEGINS*****
The user has changed these properties:

{foreach from=$param_userprops item=prop}
{foreach from=$prop item=i key=k}{assign var=$k value=$i}{/foreach}
{if $data != $param_props2update[$title]}
PROP NAME: {$title}
IS WAS: {$data}
NOW IT IS: {$param_props2update[$title]}
---
{/if}
{/foreach}
*****TEMPLATE ENDS*****