Hello Traderj!
Yes, you're right, after changing it to font parts from css it is not easy process as before. So you need to change / redeclare method getVoting in templates/base/scripts/BxBaseVotingView.php file, this 2 parts:
$sRet .= '<i class="votes_button_'.$sType.' sys-icon star-o"></i>';
and
$sRet .= '<i class="votes_button_'.$sType.' sys-icon star"></i>';
You should change it something to
$sRet .= '<img src=[path your own stars images] class="votes_button_'.$sType"/>';
and change this votes_button_ classes in common.css file in templates/tmpl_uni/css/ folder (or instead of tmpl_uni you may take correct template).
With the best regards, Leonid