Hi Rok,
Well, I have not yet produced the tutorial that will show how steps to make supporting pages in a custom feature, hopefully I will get to it soon.
But I do think I talked a bit about that in videos 7 and 8 when I talked about concepts, I'm pretty sure I explained it from a high level in context of how the forums supporting pages work.
Really, the source code for existing features is the best tutorials and should be illustrative of how to build custom features. There are examples of how to do most things you might want to do in the various existing features.
Hope it helps,
Joe