So... I'm no genuis w/ computers but I have a Mac, too. Here's what I did:
1. Put the microSD card into the SD card adaptor and put the entire thing into your Mac.
2. The icon for the card should show up on your desktop. It probably will say "No Name".
3. Double click on the icon and see what is contained w/in the card. Delete everything in the card.
4. Go to
http://www.dji.com/product/inspire-1/download and download the zipped firmware file. You can download it to your downloads directory or your desktop - somewhere you'll remember.
5. Depending on how you've set things up, the zipped file either will automatically unzip or you need to unzip it. The name of the file you want is WM610_FW_V01.02.00.14.bin
6. Do not try to decompress or modify this .bin file. Just take it and copy it to your SD card.
7. Drag the SD card icon from the desktop to the trash. This will properly remove the SD card from your Mac's desktop.
8. Remove the microSD card from your adaptor and place it back into the camera of your Inspire 1.
9. Startup your Inspire 1. It should do the rest. If you want to check out the progress, you can use the DJI Pilot app to review the progress.
To update the RC, drag the same WM610_FW_V01.02.00.14.bin file to a USB drive (probably better but not necessary that there is nothing else on it), and turn on RC. It will automatically detect the .BIN file and do a firmware update. Do not put the .BIN file in any other "folder" or directory, otherwise the RC cannot locate the file and it will not autoupdate.
Hope that is helpful.