Manual Layout of children of a Tabbed Panel in ScriptUI - adobe

Question

I'm writing a script in ExtendScript and need to have tons of checkboxes on a panel inside a tab, I can't split the panel into groups because I need to get the length property of the group.
I was wondering if anyone had experienced an issue with trying to use manual layout with Tabbed panels in ScriptUI.
Is there a way to align children of a tab panel manually?
Here's an example without tabs:
function MakeaPanel(this_obj_) {
var pan = (this_obj_ instanceof Panel)
? this_obj_
: new Window('palette', 'MainWindow',[449,210,831,576]);
CheckBGroup = pan.add('panel', [33,46,350,145], 'CheckBoxGroup', {borderStyle: "etched"});
ChkBox_1 = CheckBGroup.add('checkbox', [18,21,162,41], 'CheckBox1');
ChkBox_1.value = false;
ChkBox_2 = CheckBGroup.add('checkbox', [18,43,162,63], 'CheckBox2');
ChkBox_2.value = false;
ChkBox_3 = CheckBGroup.add('checkbox', [142,21,286,41], 'CheckBox3');
ChkBox_3.value = false;
ChkBox_4 = CheckBGroup.add('checkbox', [142,43,286,63], 'CheckBox4');
ChkBox_4.value = false;
return pan
}
var w = MakeaPanel(this);
if (w.toString() == "[object Panel]") {
w;
} else {
w.show();
}
And Here's an example with Tabs:
function MakeaPanel(this_obj_) {
var pan = (this_obj_ instanceof Panel)
? this_obj_
: new Window('palette', 'MainWindow', undefined); // [449,210,831,576]
var tpanel = pan.add ("tabbedpanel");
var MainTab = tpanel.add ("tab", undefined, "Main");
var OptionsTab = tpanel.add ("tab", undefined, "Options");
var OT_Panel = OptionsTab.add ("panel", undefined, "");
CheckBGroup = MainTab.add('panel', [33,46,350,200], 'CheckBoxGroup', {borderStyle: "etched"});
ChkBox_1 = CheckBGroup.add('checkbox', [18,21,162,41], 'CheckBox1');
ChkBox_1.value = false;
ChkBox_2 = CheckBGroup.add('checkbox', [18,43,162,63], 'CheckBox2');
ChkBox_2.value = false;
ChkBox_3 = CheckBGroup.add('checkbox', [142,21,286,41], 'CheckBox3');
ChkBox_3.value = false;
ChkBox_4 = CheckBGroup.add('checkbox', [142,43,286,63], 'CheckBox4');
ChkBox_4.value = false;
return pan
}
var w = MakeaPanel(this);
if (w.toString() == "[object Panel]") {
w;
} else {
w.show();
}