Thanks Jan. Great article about using HID, and I definitely want to try this with a PIC 18F4550 (for example) I've heard of people doing this, but have never read such a detailed article about how to achieve it. This is on my list of things to do. However, at this time, the D2xx library is working correctly on my Linux machine. The only trick is to disable the core ftdi_sio driver before running the D2xx program. You can't run one while the other is running.
Although installing libftdi didn't work, using the library supplied by FTDI was easier than I thought. I was hesitant only because everything I've done with Linux has turned out to be days long, arduous, nail-biting, hair-pulling experiences. This time, not so much.