using Assembly to create object
1.(IDAL.ISupportingData)Assembly.Load("DAL").CreateInstance("DAL.Implement.SqlServer.SupportingData");
The red color part ,you should write the the dll name of the project..not the namespace.
(IDAL.ISupportingData)Assembly.Load("DAL.Implement.SqlServer").CreateInstance("DAL.Implement.SqlServer.SupportingData");