Sam Wilson wrote:
I put all my UDFs and routines into one spreadsheet with a custom toolbar,
save it as an add-in an then distribute this to all my users. That way I can
modify and add to a master spreadsheet and then re-save it as an add-in with
version control to be redistributed.

I've considered making it an add-in but I suspect there are version
compatibility issues here - my client uses an older version of Excel,
and last time I tried to install an add-in that I had created on a
client PC, it crashed Excel. I now have another PC with the client's
build on it so I will try creating the add-in on that PC.

Making it an add-in is a barrier, though, there's a big difference
between "Open this spreadsheet and press the button on the sheet" and
"Make sure you un-install the old add-in, then install the new
version, then open this spreadsheet and press Button X on the
Toolbar".

How do your users know whether they need to update the add-in?

Phil Hibbs.