OSStartLayout

ContentPack Structure

Directories within OSPoshMods are created by default and follows this logical assignment

OSStartLayout\ALL
    Universal
OSStartLayout\$Architecture
    Start Layout for a specific Architecture

Add Content

Simply add your Start Layout XML ... easy enough

Build

New-OSBuild -SkipTask -Execute -SkipComponentCleanup -SkipUpdates -CreateISO

Sample

If you don't have a Start Layout and are looking for a clean example, use the following in your XML

<?xml version="1.0" encoding="utf-8"?>
<LayoutModificationTemplate
    xmlns="http://schemas.microsoft.com/Start/2014/LayoutModification"
    xmlns:defaultlayout="http://schemas.microsoft.com/Start/2014/FullDefaultLayout"
    xmlns:start="http://schemas.microsoft.com/Start/2014/StartLayout"
    xmlns:taskbar="http://schemas.microsoft.com/Start/2014/TaskbarLayout"
    Version="1">
    <LayoutOptions StartTileGroupCellWidth="6" />
    <DefaultLayoutOverride LayoutCustomizationRestrictionType="OnlySpecifiedGroups">
        <StartLayoutCollection>
            <defaultlayout:StartLayout GroupCellWidth="6" xmlns:defaultlayout="http://schemas.microsoft.com/Start/2014/FullDefaultLayout">
                <start:Group Name="Main" xmlns:start="http://schemas.microsoft.com/Start/2014/StartLayout">
                    <start:DesktopApplicationTile Size="2x2" Column="0" Row="0" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Computer.lnk" />
                    <start:DesktopApplicationTile Size="2x2" Column="2" Row="0" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Control Panel.lnk" />
                    <start:DesktopApplicationTile Size="1x1" Column="0" Row="2" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Run.lnk" />
                    <start:DesktopApplicationTile Size="1x1" Column="1" Row="2" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Command Prompt.lnk" />
                    <start:DesktopApplicationTile Size="1x1" Column="2" Row="2" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\Windows PowerShell\Windows PowerShell.lnk" />
                </start:Group>
            </defaultlayout:StartLayout>
        </StartLayoutCollection>
    </DefaultLayoutOverride>
    <CustomTaskbarLayoutCollection PinListPlacement="Replace">
        <defaultlayout:TaskbarLayout>
            <taskbar:TaskbarPinList>
                <taskbar:DesktopApp DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\File Explorer.lnk" />
                <taskbar:DesktopApp DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\Accessories\Internet Explorer.lnk"/>
            </taskbar:TaskbarPinList>
        </defaultlayout:TaskbarLayout>
    </CustomTaskbarLayoutCollection>
</LayoutModificationTemplate>

Results