Have you tried looking here?

That's what i just find out, (The registration key entered is a Free key, not a Premium key. DVD Profiler no longer requires free keys).

So what can i do next.

As bdixon says, just download the new version and give it a go!
Please note that if you add more than 50 DVDs then certain parts of the program become restricted (there's a list somewhere, try "Products" above I think), so try it with less first.
If you like the new version, buy it! 
The way the dollar is at the moment, you'll be getting a bargain.

Edit: one other thing, you don't need to remove the old version from your PC to run and use the new one. You'll just find the old database is no longer updated so will become more and more out of date.