Hi Mikhail,
one feature of OpenTM2 may be of interest for you (unfortunately there is a bug in it not yet fixed) - you can export an OpenTM2 folder as an XLIFF-FOLDER. The XLIFF-output would then contain all documents of the folder (source and target) as well as a bunch of meta-information.
It looks like this (short excerpt):
<?xml version="1.0" encoding="UTF-8" ?>
<xliff version="1.1" xmlns="urn:oasis:names:tc:xliff:document:1.1" xmlns:tmgr="
http://www.ibm.com">
<file datatype="html" original="count01.htm" source-language="en-US" target-language="de-DE" tool="OpenTM2">
<header>
<tmgr:properties>
<tmgr:folder>XLIFF_TEST</tmgr:folder>
<tmgr:markup>IBMHTM32</tmgr:markup>
<tmgr:sourcelang>English(U.S.)</tmgr:sourcelang>
<tmgr:targetlang>German(reform)</tmgr:targetlang>
<tmgr:shortname>COUNT01H.000</tmgr:shortname>
<tmgr:shipment>1</tmgr:shipment>
</tmgr:properties>
</header>
<body>
<trans-unit id="6" translate="yes" tmgr:segstatus="XLATED">
<source>Test translation</source>
<target state="translated">Test-Übersetzung</target>
<count-group name="word count">
<count count-type="word count" unit="word">2</count>
</count-group>
</trans-unit>
<trans-unit id="66" translate="yes" tmgr:segstatus="XLATED">
<source>This is a small test 1 sentence.</source>
<target state="translated">Dies ist ein kleiner Test-1 Satz.</target>
<count-group name="word count">
<count count-type="word count" unit="word">6</count>
</count-group>
</trans-unit>
</body>
</file>
</xliff>
Would this something be you are looking for? Actually our dev. resources are tied to most important developments, but during 2013 I could imagine that the FOLDER XLIFF bug gets fixed.
AND: when I'm talking about "cooperation", then I mainly aim for getting contributors to the OpenTM2 project. It may be any help to improve the usage of OpenTM2, because our main goal is to make OpenTM2 a representative OPEN SOURCE application supporting all most important open standards such as TMX, TBX, SRX, XLIFF etc. And our goal is to become platform independent, so that OpenTM2 not only runs on WIN, but also on e.g. LINUX or OSX ect. It is also of interest, that OpenTM2 can cooperate with many applications and platforms as possible (e.g. cooperating with MT-environments).
Best regards .... Gerhard