You may not need the LASTCLIP.TXT file -- not every editor needs it. The LASTCLIP.TXT file is primarily for the camera so it doesn't create conflicting filenames.
I read in Barry Green's HVX guide that you will not be able to import into FCP without the lastclip.txt. I did a test. I have not been saving/copying any of the lastclip.txt files to my archive hard drive. FCP imported and appears to play back footage without fail.
