How would you debug an application that retrieves data via PI-SDK without access to an OSIsoft PI Server?

I would like to know whether there are any practical software options or development approaches  for debugging applications that integrate with the OSIsoft PI Server without purchasing a licence for the complete product, e.g., test bed.

We have a data management application written in Delphi 7 which retrieves data from the PI server via the OSIsoft PI Software Development Kit version 1.3.2.  The API is imported via a type library.  The key interface used for our data access is IPICalculation using the Calculate and ExpressionSummaries methods.  We also obtain the values from the object model using the RecordedValues method of the PIData object for a given point.

Our basic approach is to retrieve the values for a given tag, called a "trigger", over a period beginning from when the server was last queried through to the current time.  This period is divided into time intervals based on when this tag changes value.  The values for each expression are then evaluated over each of these intervals.  The data is then written to a CSV file.