Thanks. I wasn't sure which forum this belonged to.
It looks like Entrouage does the same thing as Mail. When you double click, it goes into Saved Attachments in the Documents folder. Then you have to go to the Finder, Documents, Microsoft User Data, Saved Attachments.
I was thinking of sending pictures after zipping. I send to both Mac and PC users. But it looks like it is some work for the receiver. I wonder why a double click just doesn't open it up for viewing.