An update. The print server is now recognized on the network as a wireless device rather than just through the ethernet connection. These are the steps I have taken to get to this point since yesterday:
1. Flashed the device with the latest firmware v1.24.
2. Wound up having to reset to factory defaults; it did retain the firmware update (as one would expect).
3. Left the printer entirely out of the equation since printing was not the issue, connectivity was. Disconnected device power, reconnected, reattached direct ethernet.
4. Configured Networking Settings under the setup tab. Selected static, entered the fixed IP to which it'd been assigned, configured the gateway IP, saved.
5. Configured Wireless Settings under the setup tab. Wireless on (obviously), manually entered the SSID; selected the encryption type and the key, and (for my network though perhaps not yours) selected Infrastructure and SuperG mode disabled.
6. Rebooted. Disconnected direct ethernet. The router was still identifying it as a wired connection even after a refresh so I recycled the router, then recycled the device. The DLink was now wireless and recognized on the network.
7. I moved it to the destination and connected the printer. It was recognized and accessible over the network. Since print drivers were already configured for the laptop from a previous install attempt, no further configuration of the printer or its drivers was necessary.
8. From the Scan tab accessible from http://[DLink device hostname] I was able to scan. Notably, the Epson scan application that comes with the multifunction printer cannot be used and the options available through the DLink web interface are primitive, offering only BMP or PDF output, and those as a right-click/Save Image As option. But it works. The "select scan area" is kludgy, requiring left mouse button to frame the desired scan area, then a right-click on the title bar to free the mouse. I will need to convert the images to JPG format, which adds another step.
9. Wireless printing works as one would expect, through the File/Print menu option or the Print button, with no DLink app visibly needed to intervene.
The only concern I have is that since this was the most persnickety device I've had to configure for the home network in a long time, I want to monitor the situation and see if it retains network visibility if the router is rebooted or the printer is recycled or if the print server loses power and is then restored. Network devices should perform under such circumstances without intervention.
An option that I would like to see added to the Wireless Settings is selection of which wireless channel is in use. The device has been working for half an hour now and that setting wasn't needed, but with a device sufficiently annoying to get up and running, all normal configuration options should be available to help rule them out as possible sources of conflict during initial configuration.