@cchang that looks to be the older 4.0 version. Think that came out in 2010. Their current one is V4.3.13. I've got one now at 4.3.09 but testing to make sure its working and won't bomb my demo site.
Feature wise it looks to be doing most of the same work as Youst SEO. But it automatically underline your keyword phrase for you. At the very least I'm looking for the code to remove updating since you can't with out registration information. But for now it seems to be working.
I doubt it would. I tried upgrading the one I have and it couldn't do it automatically, and I have to do the manual method with a login. But you're feeling frisky enouh to try the on I've got it'll be on your shoulders. A) I'm running on ambient so my skills a re a little sluggish. B) I stopped main level programming years ago. Most of it is Greek to me but I can still read it properly.
The files were retrieved from someones unprotected uploads folder on WP.
It reads in one of the file:
Version: 4.3.09
Author: Daniel Tan
I've scanned it with VirusTotal and Comodo, and both came back clean. But don't mean much since you don't know me. Do you own scans, make your own conclusions.
Did it work for me? Well so far it has.
Will it update, No.
Is it nulled, highly doubt it.
Try it on a test server and good luck. You at your own risk.