There are two examples in the manual, one for CD and the other for P2P. Which one are you using as your reference?
I used CD as my reference and modified this example to apply for my circuit in 28nm process. But the result was no pin pair between IO and VDD to be exported because the type of the up diode in 1st-esd is pdio_hia (high current diode). The tools cannot recognize this type of device as a normal diode.
The code has to be modified to suit your design. Currently, the CD example code is set up to check resistance between top-level ports and MOS gate pins and between MOS gate pins. So the example doesn't pertain to diodes in its original form.
Firstly, are your diodes type D or are they MOS diodes?
Secondly, the init proc has to be modified so that path type propagation occurs for the proper nets and devices. In the original example, path types are only propagated across resistors.