0.6.2, ffmpeg, and MKV files

I realize this is not strictly an ffmpeg forum, but:
(before I take this q. elsewhere,
...)
Is there some difference in 0.6.2 and ffmpeg affecting MKV files?
I noticed that some MKV files with MPEG 2 video stopped working. (ffmpeg.exe dated 1/31/2012).
The same files work fine with 0.6.2 and an older version of ffmpeg.exe dated 9/25/2011.
They also work fine with a patched version of ffmpeg posted by Cerberus in the Panasonic Forum.
There is a post to 0.6.2, ffmpeg and MKV here, which may be related:
viewtopic.php?f=10&t=5182
There is not much information in the serviio log, but invoking ffmpeg.exe dated 1/31/2011 from the command line with the same arguments does show errors.
Can someone here throw me a crumb (b/f I waste too much time on this) ?
(before I take this q. elsewhere,

Is there some difference in 0.6.2 and ffmpeg affecting MKV files?
I noticed that some MKV files with MPEG 2 video stopped working. (ffmpeg.exe dated 1/31/2012).
The same files work fine with 0.6.2 and an older version of ffmpeg.exe dated 9/25/2011.
They also work fine with a patched version of ffmpeg posted by Cerberus in the Panasonic Forum.
There is a post to 0.6.2, ffmpeg and MKV here, which may be related:
viewtopic.php?f=10&t=5182
There is not much information in the serviio log, but invoking ffmpeg.exe dated 1/31/2011 from the command line with the same arguments does show errors.
Can someone here throw me a crumb (b/f I waste too much time on this) ?