You've created external rules containing .NET assemblies in the form of DLLs, but would like to set the default path of these files to a network drive, rather than the default local directory of:
C:\Program Files\Autodesk\Inventor <version>\Bin\iLogicAdd
Solution:
Go to the Tools tab and expand the Options panel (by clicking the small black arrow) and then you will then see the iLogic Configuration button. When you click this button it will bring up the Advanced iLogic Configuration dialog box, where you can set the DLL directory path. You can also add external rule directories and change the default file extension for external iLogic rules in this dialog box.
Look for more iLogic examples on this blog or in the chapter dedicated to iLogic Basics in the next edition of Mastering Autodesk Inventor book (due out in June of 2011 if all goes well).