To import a .MTS file into the Log and Transfer window the file must remain in its original file structure. Meaning, when you are ready to get the files off the card you must bring everything on the card over and not re-arange things. All of those files that come with it that look like junk tell FCP what the clips are. I think you need to check out this tutorial by Shane Ross:
http://library.creativecow.net/articles/ross_shane/p2_workflow.php
Stephen Smith
Utah Video Productions
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