New Post: Create a MSU import feature

Here's an example from my documentation:

Install Command:
Windows 7:

%systemroot%\system32\dism.exe /online /add-package /packagepath:.\Windows6.1-KB2462317-v2-x64.cab /quiet /norestart /logpath:%systemroot%\temp\KB2462317.log /loglevel:2

Windows Vista:

%systemroot%\system32\pkgmgr.exe /ip /m:.\Windows6.0-KB2462317-x64.cab /quiet /norestart

Installed Detection:
windows version equalto 6.0/6.1
select * from Win32_QuickFixEngineering where hotfixid = "kb2462317"

Update File:
CustomUpdateEngine.exe
Additional Files:
Windows 7:

7-x64-2880-R2-x64\kb2462317.xml
7-x64-2880-R2-x64\Windows6.1-KB2462317-v2-x64.cab

Windows Vista:

Vista-x64-2008-x64\kb2462317.xml
Vista-x64-2008-x64\Windows6.1-KB2462317-v2-x64.cab

Update Info:
Vendor Name:

Microsoft

Product Name:

Windows

Title:

Update for Windows 7 x64 and 2008 R2 x64 (KB2462317)
Update for Windows Vista x64 and Windows Server 2008 x64(KB2462317)

Description:
This hotfix fixes the following issue:
When printing to a networked XPS printer, you experience a longer time than usual to print the documents. For example, it may take from 5 to 10 minutes to print a document that usually takes 10 seconds to print. Additionally, some large spool files that are several megabytes in size are generated when the print jobs are processed.
More Info URL:

http://support.microsoft.com/kb/2462317

Package Type:

Update

Reboot Behavior:

CanRequestReboot

Return Codes:

{
  Value: 0
  Result: Succeeded
  Need Reboot: Unchecked
}
{
  Value: 3010
  Result: Succeeded
  Need Reboot: Checked
}

Command Line:

\actionfile=kb2462317.xml

Update is installed:
Windows 7 x64/Server 2008 R2 x64:

Load the rules file "installed 6.1.rules" into the Update level rules AND section

Windows Vista x64/Server 2008 x64:

Load the rules file "installed 6.0.rules" into the Update level rules AND section

Check "Delete Rules at Package Level"

Update is installable:
Windows 7 x64/Server 2008 R2 x64:

Load the rules file "installable 6.1.rules" into the Update level rules AND section

Windows Vista x64/Server 2008 x64:

Load the rules file "installable 6.0.rules" into the Update level rules AND section

Check "Delete Rules at Package Level"
Publish update and make visible in WSUS console

I extracted the files
7-x64-2880-R2-x64\Windows6.1-KB2462317-v2-x64.cab
Vista-x64-2008-x64\Windows6.1-KB2462317-v2-x64.cab
from the MSU using 7zip, but they can also be extracted using expand.

Here are the files referenced above:
7-x64-2880-R2-x64\kb2462317.xml

<CustomUpdate>
<Action>
<ElementType>CustomUpdateElements.VariableElement</ElementType>
<Name>Return Code</Name>
<Type>Int</Type>
<ID>37311fe4-0323-438d-8723-3edd6ea1c357</ID>
</Action>
<Action>
<ElementType>CustomUpdateElements.ExecutableElement</ElementType>
<PathToExecutable>%systemroot%\system32\dism.exe</PathToExecutable>
<Parameters>/online /add-package /packagepath:.\Windows6.1-KB2462317-v2-x64.cab /quiet /norestart /logpath:%systemroot%\temp\KB2462317.log /loglevel:2</Parameters>
<KillProcess>True</KillProcess>
<TimeBeforeKilling>10</TimeBeforeKilling>
<Variable>37311fe4-0323-438d-8723-3edd6ea1c357</Variable>
</Action>
<Action>
<ElementType>CustomUpdateElements.ReturnCodeElement</ElementType>
<ReturnCodeMethod>Variable</ReturnCodeMethod>
<StaticReturnCode>0</StaticReturnCode>
<Variable>37311fe4-0323-438d-8723-3edd6ea1c357</Variable>
</Action>
</CustomUpdate>

Vista-x64-2008-x64\kb2462317.xml

<CustomUpdate>
<Action>
<ElementType>CustomUpdateElements.VariableElement</ElementType>
<Name>Return Code</Name>
<Type>Int</Type>
<ID>37311fe4-0323-438d-8723-3edd6ea1c357</ID>
</Action>
<Action>
<ElementType>CustomUpdateElements.ExecutableElement</ElementType>
<PathToExecutable>%systemroot%\system32\pkgmgr.exe</PathToExecutable>
<Parameters>/ip /m:.\Windows6.0-KB2462317-x64.cab /quiet /norestart</Parameters>
<KillProcess>True</KillProcess>
<TimeBeforeKilling>10</TimeBeforeKilling>
<Variable>37311fe4-0323-438d-8723-3edd6ea1c357</Variable>
</Action>
<Action>
<ElementType>CustomUpdateElements.ReturnCodeElement</ElementType>
<ReturnCodeMethod>Variable</ReturnCodeMethod>
<StaticReturnCode>0</StaticReturnCode>
<Variable>37311fe4-0323-438d-8723-3edd6ea1c357</Variable>
</Action>
</CustomUpdate>

installable 6.0.rules

<bar:Processor Architecture="9"/><bar:WindowsVersion Comparison="EqualTo" MajorVersion="6" MinorVersion="0"/><lar:Not><bar:WmiQuery Namespace="root\CIMV2" WqlQuery="select * from Win32_QuickFixEngineering where hotfixid = &quot;kb2462317&quot;"/></lar:Not>

installable 6.1.rules

<bar:Processor Architecture="9"/><bar:WindowsVersion Comparison="EqualTo" MajorVersion="6" MinorVersion="1"/><lar:Not><bar:WmiQuery Namespace="root\CIMV2" WqlQuery="select * from Win32_QuickFixEngineering where hotfixid = &quot;kb2462317&quot;"/></lar:Not>

installed 6.0.rules

<bar:WmiQuery Namespace="root\CIMV2" WqlQuery="select * from Win32_QuickFixEngineering where hotfixid = &quot;kb2462317&quot;"/><bar:Processor Architecture="9"/><bar:WindowsVersion Comparison="EqualTo" MajorVersion="6" MinorVersion="0"/>

installed 6.1.rules

<bar:WmiQuery Namespace="root\CIMV2" WqlQuery="select * from Win32_QuickFixEngineering where hotfixid = &quot;kb2462317&quot;"/><bar:Processor Architecture="9"/><bar:WindowsVersion Comparison="EqualTo" MajorVersion="6" MinorVersion="1"/>