The script do a good job. But be aware of user complains .... The counter is lower then in the old boards. And it is clear from what this comes:
In the old board all posting was counted from start. Then old postings get purged. The User was imported and his existing postings counted with this script. This result in a lower posting counter.
Its by design and correct. But you must tell it the user.
For my top 10 poster I go to the databases and correct the counter by hand Ä(because they dont let me sleep until this was done)