Dimenticavo, ecco lo script:

on (release) {
getURL("javascript:window.open('sonya_mariani.htm' ,'SONYA_MARIANI','width=715\" add wdth add \",height=555\" add hdth add \",resizable=yes\",top='+((screen.availHeight/2)-(\" add hdth/2 add \"))+',left='+((screen.availWidth/2)-(\" add wdth/2 add \"))); void(0);");
}

Ciao e grazie lo stesso!!!