Question

How could I make both templates work in the same XSLT file?

Source XML

<?xml version="1.0" encoding="utf-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
    <Fragment>
        <DirectoryRef Id="WixSlave.Binaries">
            <Component Id="cmpA1D1BF677641BE2AE700859D8256B0FC" Guid="{B0BF9CBD-8A5D-43C1-B9DE-0A1B5A6BD1DE}">
                <File Id="filC2827DDF7874712A62423151FBE8CE34" Source="$(var.WixSlave.TargetDir)\WixSlave.exe" />
            </Component>
            <Component Id="cmpBC6AB890535757A915C99A10445CC74E" Guid="{8726FF82-808A-4736-AD0A-C804A34E494B}">
                <File Id="fil7BD5BE5CD71AC92FF47D1D51A99FEE05" Source="$(var.WixSlave.TargetDir)\WixSlave.exe.config" />
            </Component>
        </DirectoryRef>
    </Fragment>
    <Fragment>
        <ComponentGroup Id="WixSlave.Binaries">
            <ComponentRef Id="cmpA1D1BF677641BE2AE700859D8256B0FC" />
            <ComponentRef Id="cmpBC6AB890535757A915C99A10445CC74E" />
        </ComponentGroup>
    </Fragment>
</Wix>

Only Folder Template Produces Desired Output, Registry Template “Ignored”

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns="http://schemas.microsoft.com/wix/2006/wi" xmlns:wix="http://schemas.microsoft.com/wix/2006/wi" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <!-- Copy all attributes and elements to the output. -->
    <xsl:template match="@*|*">
        <xsl:copy>
            <xsl:apply-templates select="@*"/>
            <xsl:apply-templates select="*"/>
        </xsl:copy>
    </xsl:template>

    <!-- Folder Template -->
    <xsl:template match="wix:Wix/wix:Fragment/wix:DirectoryRef">
        <DirectoryRef Id="TARGETFOLDER">
            <xsl:copy-of select="*"/>
        </DirectoryRef>
    </xsl:template>

    <!-- Registry Template -->
    <xsl:template match="wix:Wix/wix:Fragment/wix:DirectoryRef/wix:Component">
        <Component>
            <xsl:apply-templates select="@*|*"/>
            <RegistryValue Root="HKCU" Key="Software\[Manufacturer]\[ProductName]" Name="toBeVariableKey" Type="integer" Value="1" KeyPath="yes"/>
        </Component>
    </xsl:template>
</xsl:stylesheet>

Registry Template Works Fine Without Folder Template

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns="http://schemas.microsoft.com/wix/2006/wi" xmlns:wix="http://schemas.microsoft.com/wix/2006/wi" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <!-- Copy all attributes and elements to the output. -->
    <xsl:template match="@*|*">
        <xsl:copy>
            <xsl:apply-templates select="@*"/>
            <xsl:apply-templates select="*"/>
        </xsl:copy>
    </xsl:template>

    <!-- Registry Template -->
    <xsl:template match="wix:Wix/wix:Fragment/wix:DirectoryRef/wix:Component">
        <Component>
            <xsl:apply-templates select="@*|*"/>
            <RegistryValue Root="HKCU" Key="Software\[Manufacturer]\[ProductName]" Name="toBeVariableKey" Type="integer" Value="1" KeyPath="yes"/>
        </Component>
    </xsl:template>
</xsl:stylesheet>

Answer 1

You have to let the chain of template matching continue. Changing the folder template in the following way will get you going:

<!-- Folder Template -->
<xsl:template match="wix:Wix/wix:Fragment/wix:DirectoryRef">
    <DirectoryRef Id="TARGETFOLDER">
        <xsl:apply-templates select="*"/>
    </DirectoryRef>
</xsl:template>

so basically you have to let XSLT know that you need to continue traversing the nodes further down.

UPDATE: and remove the copy-of instruction if you don’t want the duplication of the Component node