In Savannah, I went first to the Office Depot to try to get a serial-device to USB converter. No luck, even after I found a salesperson in the department. The kind gentleman suggested some computer shop somewhere in town. Since the streets he mentioned where not on the limited map I had, I tried next door at Best Buy and found a Belkin device that was supposed to do it. These devices have a bad reputation, and the salesperson did not seem to think it was the right device, but I had no choice so I took my chances with the one that was stil in the box, instead of the one returned to store by an unhappy customer.
From Savannah over Beauford and Charleston to Georgetown. I stopped at Fort Moultry, most famous for starting the civil war by shelling Fort Sumter.
Checked in the Hampton in Georgetown and tried out the Belkin device. The package said it requires a USB 1 or 2 port; the instructions inside the almost indestructable packaging specified a USB 2 port only. They did not have anything about what to do if the instructions failed, which is exactly what they repeatedly did. Not even a toll support number. To my surprise, I got it to work by replacing the Belkin USB 2 hub driver twice with the generic USB one. Trip maps can now be downloaded from the GPS.
Unfortunately, due to a low or poor battery in my digital camera, the pictures were apparently not saved.