Template/Assets/Layout.xml

<LayoutModificationTemplate xmlns:defaultlayout="http://schemas.microsoft.com/Start/2014/FullDefaultLayout" xmlns:start="http://schemas.microsoft.com/Start/2014/StartLayout" Version="1" xmlns="http://schemas.microsoft.com/Start/2014/LayoutModification">
  <LayoutOptions StartTileGroupCellWidth="6" />
  <DefaultLayoutOverride>
    <StartLayoutCollection>
      <defaultlayout:StartLayout GroupCellWidth="6">
        <start:Group Name="Productivity">
          <start:Tile Size="2x2" Column="0" Row="0" AppUserModelID="Microsoft.MicrosoftEdge_8wekyb3d8bbwe!MicrosoftEdge" />
          <start:Tile Size="2x2" Column="2" Row="0" AppUserModelID="Microsoft.WindowsStore_8wekyb3d8bbwe!App" />
        </start:Group>
      </defaultlayout:StartLayout>
    </StartLayoutCollection>
  </DefaultLayoutOverride>
</LayoutModificationTemplate>