Hello, I bought the pro subscription simply so I could have fun with some wild homebrew creations. I have added tons of subclasses to my collection, but none of them are showing up. Is there some key component I'm missing? Maybe there are prerequisites I'm not seeing or a feature I'm not switching? I have looked through multiple subclasses and my optional features and cannot find any conflicting switches or prerequisites though. 

On the “Home” tab of the Character builder, the toggle next to “Homebrew Content” needs to be on (red, to the right).

Thank you for the reply, however, I have already done this and my subclass options are still nonexistent. Any other advice?

What class is the character and what level is the character? Most classes choose their subclass at 3rd level. So if your character is not the correct level to choose a subclass you won’t see any subclass options for it.

I have been attempting to add a rogue subclass, and I have messed with the leveling as well. He is currently level 5 and I still cannot see any options available under the optional class features. 

Oh my goodness, I have figured it out. To add my subclass I just continue through the main class options and do not need to mess with the optional class feautures. My bad and thank you for the help.

That’s because “Optional Class Features”  are just that, optional. choosing a subclass isn’t optional at all, it’s actually mandatory, and part of each base class standard rules.