All valid accounts from the original forum have been transfered to the new one along with any posts that still existed. You will need to reset your password as it wasn't possible to transfer those as they are all encoded. Click on the "forgot your password?" link and enter the email address you would have had in use on the old forum. You will then receive an email with a verification link that you can click to reset the password on the new account.
If you didn't have a valid email account linked to your original account (tut tut!), then simply send me a PM on the old forum so I can check it is you, I can then update your email and you can then use the above procedure to activate your new account.