the code is not all in english, I guess this is is,

function CenterNewWindowOnScreen(action)
{
var wf = "";
wf = wf + "width=" + action[3];
wf = wf + ",height=" + action[4];
wf = wf + ",resizable=" + (action[5] ? "yes" : "no");
wf = wf + ",scrollbars=" + (action[6] ? "yes" : "no");
wf = wf + ",menubar=" + (action[7] ? "yes" : "no");
wf = wf + ",toolbar=" + (action[8] ? "yes" : "no");
wf = wf + ",directories=" + (action[9] ? "yes" : "no");
wf = wf + ",location=" + (action[10] ? "yes" : "no");
wf = wf + ",status=" + (action[11] ? "yes" : "no");

/*zuweisung der bildschirmbreite und -hoehe zu den variablen sw und sh*/
var sw=screen.width;
var sh=screen.height;

/*festlegung der groesse von neufenster*/
var neubreite=action[3];
var neuhoehe=action[4];

/*berechnung der position von neufenster*/
var positionleft=(sw-neubreite)/2;
var positiontop=(sh-neuhoehe)/2;

/*oeffnen von neufenster mit uebergabe der parameter*/
Neufenster=window.open(action[1],action[2],wf);

/*nachtraegliches positionieren von neufenster*/
Neufenster.moveTo(positionleft,positiontop);

Neufenster.focus();