Print Airport Express configuration?

You can export the base station's configuration file, and then, import it into another base station. What I haven't verified is if it would include all of the DHCP Reservations and Port Mapping settings.

You can give it a try yourself to see if it does. The exported "<base station name>.baseconfig" file can be read with a text editor or printed out.

To export/import the base station configuration settings:

• Run the AirPort Utility.
• Select the source base station, and then, select Edit.
• From the utility's menu bar, select File > Export Configuration File...
• Enter a desired name or leave the current base station name.
• Note where it will be saved. By default, it should be the Desktop.
• You can elect to encrypt it is you so wish.
• Click on Save.
• From the AirPort Utility, select the destination base station, and then, select Edit.
• From the utility's menu bar, select File > Import Configuration File...
• A pop-up window should appear with the contents of the Desktop.
• Look for a file with the extension of "baseconfig." Select it, and then, click on Open.
• Click on Update and allow the destination base station to restart.

Not exactly what you ask for, but another possible option to try if the text editor does not provide you with a clear report of the DHCP Reservation and Port Mapping settings.....

Open up AirPort Utility and go to the section with the details that you need

Take a screenshot of each page, (Control--Shift--4, position the cursor at the upper left corner of the area that you want to copy, then drag down and to the right to select and then release the mouse button) which will result in a PDF file of the selected area on your Mac's desktop

Print the PDF(s) if you need to do so

You can open the .baseconfig file in most text editors, and the DHCP reservations are in XML text.