Well, like I said, you really HAVE to go to 7.5.5. The import script won't work with 7.0.2.
What you should do is grab 7.5.5 and install it into a new directory, something other than your 6.5.5 directory. Then bring up the importers/threads_import.php, fill in the info it asks for and then let us know if you get any specific errors.
