I responded privately to this as it was also addressed to my personal email. Do you have any other questions from my private response? You can post them here if you like since if other people have ideas and opinions, I'm happy to hear them too.

I've tried the wiki links a few times and they seem to work for me. You may have tried at a bad time as it happens periodically the fpc sites get busy. Here is the wiki link to my tutorial on OOP in FPC. It is a general intro with 4 sublinks to more detailed information covering chapters 5,6,7, and 8 - of which I have completed only the one for chapter 5 so far. I'm still learning the finer points of Classes dialect myself. Although I did not provide/embed the full source code in the tutorial, the code snippets are from an actual program I compiled and ran without further editing so they should work once you build up the programs as you proceed. They are generic (doesn't even use objfpc for the chap 5 Object dialect) so should run on any platform/IDE without much , if any problems. - R

Programming with Objects and Classes - Free Pascal wiki