I'm happy to report that I was able to update my Alpine HD138BT with my Macbook Air.
The first time I tried, weeks ago, I was able to set up the bluetooth connection, but the Alpine would not connect to the Air even after repeated attempts.
Yesterday, I set up the connection and the two connected on the first try. I then went through the instructions (the OS X folders, windows, etc., that correspond to the Windows 8 versions that are described in the instructions are pretty easy to figure out) to update the firmware.
On the first attempt, the file transfer completed, but the HU was stuck on the "don't touch any button" message. I eventually turned the car off, and when I turned it back on the firmware version was still 1.14.00. I attempted to connect the devices again, but this time the connection failed; yet when I tried to transfer the file again, the transfer proceeded, so as someone else posted above, sometimes the devices are connected even if the message from the HU indicates otherwise. Once again, I got stuck on the "don't touch any button" message, but when I turned the car off and on again, the firmware version showed 1.27.00. I checked, and all BT audio functionality was restored.
Initially, I blamed Apple for this cluster****. But I'm now 100% in the camp blaming the individual manufacturers. On top of that, I think Alpine handled this horribly. It is absolutely absurd to set up a FW update like this, and only provide instructions for one type of operating system, and to not even test it with another operating system (as they claimed to someone above). With a USB port on the front of the unit, the process should have been designed as, 1) copy the file to a memory stick, 2) insert the memory stick into the HU, 3) select the firmware update option. Done. Instead, this is one of the worst-designed software update processes I've ever seen. Ever.
I hope Alpine is embarrassed.
Rich