We are developing a GUI component which needs to receive data from the calling application so that defaults and instructions can be conveyed to the GUI component. The GUI component contains several forms on which the data will be displayed.The GUI component also needs the ability to send user-specified input data back to the calling application so it can be passed on to other components. We can define an XML object as a way to pass data. If the GUI component is a DLL, another option is to pass information as properties of a class in the DLL. What are the issues involved if we pass the data as XML or as properties of class. Please provide your suggestions/inputs covering the ease of developing and maintaining the code for future use also. The GUI Component will be developed in VB6.0

Thanks a lot in advance