Even if the hardware is damaged, it will log some number provide the setup is correct. If there were a hardware problem, like the Analog to Digital Converter got fried, it would read some number all the time.. most likely the minimum AFR.
Here is a picture of my auxiliary. Values from 0V-5V are different for AEM, 10AFR-20AFR if I remember right, but either way make sure Delta AN1-AN2 is checked. If this doesn't help and your gauge is working then I'm not sure how where to start.
That's the problem. Aux A/D has to be checked for it to be even read by the software. They put those checkboxes there so the software can spend less time doing I/O (for things you don't even care about) thereby giving more frequent updates for data you DO care about.