I forgot to post my code:

<group id="Import" label="Import"

<box boxStyle="vertical" id="box1"
<button id="buttonL1" label="Left Top" onAction="DoSomething"/
<button id="buttonL2" label="Left Middle" onAction="DoSomething"/
</box

<box boxStyle="vertical" id="box2"
<button id="buttonR1" label="Right Top" onAction="DoSomethingy"/
<button id="buttonR2" label="Right Middle" onAction="DoSomething"/
</box

<button id="buttonB" label="Bottom" onAction="DoSomething"/

</group