The reference guide seems to be very application level.
Searching through I found the property TableProp buried deep in the PEREntityOR* classes. How would you know that you can call that as Entity.TableProp (please remember I am not a hardcore OO programmer)?
please have a look at the User Guide, section Customization - Sample. In topic “Access Property Values via Scripting Window” you will find information about how to search or use the Referece Guide document. In general, if you work with physical model, look for PER (Physical Entity Relationhip) and if you work with Oracle, look for OR* classes. (LER is for logical model).