--Breakdown: I need code to open and hide an xl workbook("UserFormSource") that contains a UserForm source code and supporting sheet whenever one of the 5 books("FreshData") that uses the userform is opened. Also need to close this hidden book ("UserFormSource") when ("FreshData") is closed.

--Details: I have a UserForm that I created that is fairly complex, but I use the form for several different books. Copying the UserForm source code into the other books is pretty simple (although I would like to centralize that as well if possible) but I have to update the reference spreadsheet (which holds various drop-down menu selections, generated e-mail bodies, contact lists and such) with fair amount of regularity.
To that end I wanted to centralize the location of the "UserFormData" sheet which I currently have copied into each of the books that I use the UserForm in (4 or 5 separate files, let's call them "FreshData"). I would Rather have one excel book ("UserFormSource") that holds the UserForm source (if possible) as well as the UserFormData sheet and have that ("UserFormSource") book open (read-only) whenever these other books ("FreshData") are opened. What i really want to do is have the source book hide itself on open, but keep the UserForm visible. I'd also like to have that ("UserFormSource") book close automatically when the book that opened it ("FreshData") closes. I would assume that I could use an Event to do this?
Also, can I do this in such a way that the UserForm can reference the UserFormData sheet in the hidden ("UserFormSource") book for the dropdowns and such while using the main book's ("FreshData") data to fill in the UserForm? I'd probably have to change all the references to indicate it's in a different workbook wouldn't I? Currently I'm just using a Sheet reference for the location of data for the dropdowns, I'm thinking I'd have to add a WorkBook reference as well? Is there anything special I'd have to do since it's not visible/active?

Thanks in advance!

Let me know if you need me to generate a sample. There's a lot of confidential data involved so I'd probably have to just whip up a fake one from scratch but i will if you need it