CHIRP

1. can you please provide the output from terminal (Applications->Utilities) for the following command: @ kextstat | grep -i pl2303 @

Maybe to be clear on one more point, after the attempted upload the radio display shows clone mode.I then have to reset the computer with a power off and reset the radio by powering off as well. Note that the memories in the radio are then erased and all setting seem to have been returned to a default. Since I have two of them I can restore the setting thankfully by cloning from my other IC80AD.

ok thanks.
Try this driver:
http://chirp.danplanet.com/projects/chirp/wiki/MacOS_Tips#-Generic-PL-2303-cables-counterfeit-andor-%E2%80%9CGeneric%E2%80%9D-If-you-arent-sure-what-kind-of-inexpensive-cable-you-have-try-this-one-first

-- Exception: --
Traceback (most recent call last):
File "/Applications/chirp-daily-20140827.app/Contents/Resources/chirp/chirpui/clone.py", line 225, in run
self.__radio.sync_out()
File "/Applications/chirp-daily-20140827.app/Contents/Resources/chirp/chirp/icf.py", line 594, in sync_out
clone_to_radio(self)
File "/Applications/chirp-daily-20140827.app/Contents/Resources/chirp/chirp/icf.py", line 395, in clone_to_radio
raise errors.RadioError("Failed to communicate with the radio: %s" % e)

RadioError: Failed to communicate with the radio: Out of sync with radio¶

Clone failed: Failed to communicate with the radio: Out of sync with radio

so this could be caused by a number of things but I would try the following:

1. try different usb ports on the computer (e.g., if using front, try back; if using hub, try direct port, and vice-versa)
2. try different computer
3. try different cable

I tried different ports. Same result. I only have one cable so I guess I am out of luck for now. Hopefully someone will be able to fix this one day. Thanks for everyone's efforts, its a great program for most people.

This might be the typical "Mac hates Prolific" problem.
However, a lot of Icom radios do have problems with FTDI cables (even genuine ones).
For now, you're (still) out of luck, until we can find out what in the Icom drivers causes the problem.
However, you might find something helpful in MacOS Tips - if you do, please let us know!