I never use docx or any of these other ones - of course. I just have to open them in something/anything, and then Save As a normal, old-fashioned doc - which clients and contacts can open, whatever system they've decided to buy.
I'm still using Office 2004, which is the last available version that works, and is perfectly adequate in terms of functionality.
As you saying I can get a patch for my Office 04 that will open docxes and save as normal docs? On a mac?