After almost giving up on the Alinco DJ-G7 programming software (hardly ever connected to the radio or it failed halfway through reading/writing), I had another go with it yesterday.
After reading these instructions I tried changing the baud rate in Windows Device Manager to 57600 and it connected first time using a USB-serial cable (in Windows 8).
I still got the odd error when reading/writing a large number of memories at once but this may be the radio at fault and not the software, see this page about some alternative programming software.
I didn't think any applications still used the Windows serial port settings, usually it is set somewhere else and the Device Manager page was not something you would ever have to change.
I find it easier to export the Alinco's memory data to a CSV file and edit it in Excel, that way the memories can be programmed in on the go, uploaded and then sorted by frequency etc.
Today I tried connecting my Icom IC-2800 to the PC. I had the CS-2800 programming software but never had any success in getting it to connect. The Icom OPC-478 cable is the same wiring as the USB cable I used to program the Alinco DJ-G7 (a single data line on the ring of a 3.5mm jack plug), so I tried that cable.
I have 2 of these cables which should be compatible with the OPC-478. The first one did not work, I thought it might be something to do with running the old Icom software in Windows 8 or the baud rate (I'd got suspicious about the Windows baud rate settings after getting the Alinco to work) but then I read this message where the writer tried several cables and only one worked. I tried my other OPC-478 type cable and once the COM port was changed to COM2 (the CS-2800 software only allows COM1 to COM4), it worked perfectly. I even tried the Windows baud rate at both 4800 and 9600 and it made no difference.
What is the difference between the 2 cables? The only thing I can think of is that Cable 2 had the ring of the jack plug at 2.78V when not connected to any radio, and the non-working Cable 1 had this at 3.3V.