Importing into a CAT tool is a fairly simple matter: when the languages of interest are specified, the respective tool will extract the data desired. I tested this in memoQ (53 K entries imported) and SDL Trados Studio 2009 (48 K entries imported) with English and Russian, and the process was quite painless. I presume the difference of about 20,000 translation units read and the number imported have to do with redundancies and memoQ and SDL Trados Studio interpret these in a slightly different manner, but I don't really know. I also tested OmegaT, but unfortunately it chokes on the file when copied into the TM directory:
The following suggestion was offered by Yves Savourel on the Yahoogroups OmegaT list:
If you work on Windows, you can drop/drop the TMX file in Olifant (the "old"
.NET version: http://sourceforge.net/projects/okapi/files/)
That will show you the 74,070 entries in 6 languages in it.
Then do "File > Export", select the output file name, and then the 2 languages
you want in that new TMX file.
This tip is good for everyone, of course, not just OmegaT users. The Okapi tools are excellent and free for maintaining TMs when the tool providers can't be bothered so far to offer decent facilities for maintaining the data in their software (not naming any names here, but you know who you are....)