I see, I'm in the same situation as you.My Wii U is on 5.4.0 and not on 5.3.2
Without a way to test stuff, it's useless for me ._.
Alternatively you could get a browser exploit for something like Internet Explorer 6 and experiment with it. That way you learn more effectively because on another device it's less convenient. This suggestion seems dumb because it's not the Wii U but you'll see that it's all pretty similar nevertheless.