I have used a value of 6136 for btn.FaceId. This works fine in Excel
2003, and I think it's OK in XL2002, but a user with XL2000 is
reporting Error 80004005. I got them to change it to a smaller number
and it worked OK (except obviously they get the wrong icon).
Any idea what is causing this error?
Is there a maximum value for FaceId, that varies depending on the
version of Excel? If so, what are the limits for the different
versions?
Number 6136 isn't particularly good for what I want anyway. Can anyone
suggest a better icon for launching a tool that performs various types
of analysis to identify and label certain data points in an Excel
Chart?

Thanks
Phil.