I couldn't figure out how to make my question any shorter, and I pretty much say it all above. But here are specifics I'm thinking about:

I'm building an XLA that will reside on a shared network drive. The network administrator has access to every user's Registry. He will grant individual users access to this XLA by placing the XLA's path in the Registry as an Add-In to be automatically referenced when the Excel Application is opened. No one will have a local copy.

I would like to use some objects that live in Type Libraries that I can't guarantee will be on every user's machine. In particular, I'd like to use the VB6 Timer object, and if possible, the .NET ArrayList object. Can I install the appropriate dlls on the network machine where the XLA resides, and set references to them from within my XLA Does the dll functionality "transfer" to the user's machine

My question refers to Excel 2000 and 2003. Thanks!