I generated script from old database, created a new database and imported all data from old database. So far so good, however, no user has execute rights for stored procedur
Create a role add this role to users, and then you can grant execute to all the routines in one shot to this role.
CREATE ROLE GRANT EXECUTE TO
EDIT This works in SQL Server 2005, I'm not sure about backward compatibility of this feature, I'm sure anything later than 2005 should be fine.