Excel cross PC/MAC compatibility

[charlie]

I am about to develop a data management application in Excel for a small business on my PC using either Excel 2003 or 2007 as I have both. This application will need to be used and updated by everyone in the company but one employee wants to buy a Mac and use Office for Macs. I foresee that the application will be quite complex as part of it will have to imitate a relational database.



Can anyone advise me of any potential problems? I already see that Office 2008 for MACs, which I presume has the equivalent functionality to Office 2007 for PCs, does not have a Macro capability. This may be a big problem for me. What other nasties are waiting for me?

I'd much appreciate any help.