I notice that I can add a reference to my own custom DLL using #r within Workbooks. I can do this with a standard WinForms DLL which means I can create working documents training new employees on how to use our own custom libraries. However if these show custom WinForms screens such as a messagebox the code 'Runs' forever. Is this by design?
Also, how do I add a reference to System.Data? Would I need to copy the DLL into the workbook folder or is there a way to add assemblies from the GAC?