It shows up in my Add Ins menu, but seems to just make Excel freeze. From the menu, looks like you need some understanding of SPC charts/statistics to begin with just to use it. i.e. not beginner friendly.
Can anyone confirm the problem?
@CalRich - What version of Excel/Office? What OS (e.g. Windows XP, Windows 7 - I'm assuming a Windows OS, but...)?
Using Excel 2007 on Windows 8 and it works OK for me. Assuming the .xla file is on your desktop, open a blank workbook in Excel, then double-click on the .xla file. In Excel, click on "Add ins" on the menu bar, and then SPC Macros on the dropdown box that appear--see the attachment.