How can I save my Micrografx Designer 4.1 (*.DS4) work from a Windows format into an i-Mac format?
You can't save the work from MD to the i-Mac because there is no application configured to run on Mac. CorelDraw is capable of opening DS4 files, but that's on Windows. On Mac, you can install Paralells Desktop to install Windows and then CorelDRAW to open the files.
Paralells Desktop: http://www.parallels.com/products/desktop/