+</section>
+
+<section>
+<title>Adding soundtracks or subtitles in different languages</title>
+
+<para>
+If you have a film that is to be dubbed or subtitled in several
+languages, the best approach with DCP-o-matic is as follows:
+</para>
+
+<itemizedlist>
+<listitem>Make a DCP with the common elements (perhaps just the video, or maybe the video and sound); this is known as the Original Version (OV).</listitem>
+<listitem>For each language, make a new Version File (VF) DCP which refers to the OV.</listitem>
+</itemizedlist>
+
+<para>
+Once you have done this, you send the OV DCP to every cinema and then
+the appropriate VF to each cinema depending on what language they want
+to play the film in. The projectionist ingests both DCPs and then plays the VF.
+</para>
+
+<para>
+The advantage of this approach is that the VF DCPs are much smaller
+than the OV since they only have the language-specific parts. If you
+are just changing the subtitles you can often ship the OV by normal
+transport means (e.g. a hard drive or high-speed download) and send
+the VF by email.
+</para>
+
+<para>
+The full details of OV and VF files are discussed in <xref linkend="sec-overlay"/>. The steps can be summarised as follows:
+</para>
+
+<itemizedlist>
+<listitem>Create a new DCP-o-matic project for the OV, as normal, adding video and perhaps sound. Make the DCP.</listitem>
+<listitem>Create a new DCP-o-matic project for the VF.</listitem>
+<listitem>Use <guilabel>Add folder...</guilabel> to add your OV DCP to the project.</listitem>
+<listitem>Select the video tab and tick <guilabel>Use this DCP's video as OV and make VF</guilabel> (you may need to select <guilabel>By video content</guilabel> for <guilabel>Reel type</guilabel> in the <guilabel>DCP</guilabel> tab).</listitem>
+<listitem>Do the same in the <guilabel>Audio</guilabel> tab if your OV has audio.</listitem>
+<listitem>Add your language-specific audio and/or subtitles and Make DCP.</listitem>
+</itemizedlist>
+
+</section>
+
+</chapter>
+
+<chapter xml:id="ch-player" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+ <title>Playing and verifying DCPs</title>
+
+ <para>DCP-o-matic includes a DCP player, and although it requires a
+ very high-speed CPU to play DCPs in full resolution, it can also
+ play DCPs at reduced resolutions with slower CPUs.</para>
+
+ <para>To use the player, start <guilabel>DCP-o-matic
+ Player</guilabel>, and load a DCP using the
+ <guilabel>Open</guilabel> option on the <guilabel>File</guilabel>
+ menu.</para>
+
+ <para>If you load a VF and/or encrypted DCP you can add your OV
+ and/or KDM using the appropriate options on the
+ <guilabel>File</guilabel> menu.</para>
+
+ <para>During playback the <guilabel>Performance</guilabel> area at
+ the bottom right of the window will give details of how many frames
+ are being dropped; these are frames that were not decoded from the
+ DCP quickly enough. If this number is high you can increase
+ performance at the cost of rendering quality by choosing an option
+ from the <guilabel>View</guilabel> menu. If you set the player to
+ decode at less than full resolution the DCP's data will be decoded
+ at this lower resolution, which is quicker than decoding at full
+ resolution.
+ </para>
+
+ <para>
+ The player also offers a simple DCP validator. To check a DCP,
+ open it and then select <guilabel>Verify DCP</guilabel> from the
+ <guilabel>Tools</guilabel> menu. This will run some basic checks to see if the DCP meets the required standards.
+ </para>
+
+</chapter>
+
+<!-- ============================================================== -->
+<chapter xml:id="ch-config" xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en">
+<title>Configuration files</title>
+
+<para>Most of DCP-o-matic's configuration is stored in an XML file called <code>config.xml</code>. This is stored in different places depending on your operating system:</para>
+
+<itemizedlist>
+ <listitem>Windows: <code>c:\Users\your_user_name\AppData\Local\dcpomatic</code></listitem>
+ <listitem>OS X: <code>/Users/your_user_Name/Library/Preferences/com.dcpomatic/2</code></listitem>
+ <listitem>Linux: <code>~/.config/dcpomatic2</code></listitem>
+</itemizedlist>
+
+<para>Possible XML tags are as follows:</para>
+
+<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="config.xml"/>