Was just updating that too! That is why it was locked.
The problem was the macros. The Mac users were using Numbers, not Excel. And the macros don't work on Google Docs. My recommendation was either to get them Office 2011 for Mac or to get the free, open source Libre Office. Compatible with Office, works with the macros, and is free.
The sharing wasn't the problem (the could use dropbox and such too), it was the macros.
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Michael Carnell - Charleston, SC