Hi,
It sounds like they did not give you a new db but they did delete the tables and stored procedures. What they missed when deleting things is maybe the User Defined Functions such as PersianDay.
What you can do is edit the file /Setup/applications/mojoportal-core/SchemaInstallFiles/mssql/2.2.7.8.config with a text editor, and just chop out the parts that create any user defined functions that the setup page complains about since they must already exist.
Hope it helps,
Joe