Info on add_edit_ui WIZARD_UI PTFs?

Topic resurrection... got another question...

When an element has glue or align attributes, what elements do those affect? The element itself, or enclosed elements?

My current case has code in the .PTF like so:

GROUP ops
{
    align = "left";
    GROUP
    {
        align = "left";
        layout = "horizontal";
        CHECK
        {
            title="Generate IRQ";
        }
        CHECK
        {
            title="Generate End-of-Packet";
        }
    }
    CHECK
    {
        title="Data read/write can block master";
    }
}

The first two check boxes appear on the same line, but they're centered, not left-justified. Just wondering what I'm missing...