Hi Rasmus,
The IO framework is very simple and it will not do much for you. It will find the IO objects, that is, objects with the IO flags set in the ClassDef object, and it will call the IO methods for an object from the specified process and plc thread.
So there are only two attributes that are mandatory, Process and PlcThread. Usually you also add Description and maybe Specification and DataSheet, but all the other attributes are data that you use and handle in the IO methods that you write in c-code. This is configuration data that you need to attach and setup the device and also data you need for troubleshooting, as errorcount, status etc.
You also have to specify the IO methods so the framework can find them, and that you do with $Method objects in the classvolume.
The way to start I think is to create a Rack and Card class and some methods and see that you can link the methods with the plc executable and that they are called when you execute the plc.
/Claes