I think the best way is that you send mail to the seller so that they support you. The problems relating to the account, only a new admin help you.
"Zamfi" doesn't give support for anything, anyway
What error message are you getting?
I got the script few months back but default admin/pass wasn't the problem.
Go to database of the script -> then user table-> then change admin pass & select datatype md5 -> and execute.
try this method If not work there are other methods too.
But I think your databse connectivity is not done properly that's why you are getting that kind of error.