Here are a couple of questions about using Add-Ins:

How can I attach an Add-In to a Workbook using VBA?

Once the Add-In is attached, how do I associate the subroutines and
functions in the add-in with events taking place in the workbook.worksheet
where it is attached? For example an on_activate event in Sheet1 of the
workbook that has an add-in attached needs to run code that exists in the
add-in.

Thanks,

Keith