Hhmmm... Although the terms may seem very clear, I see this license getting more and more blurry and make it close to impossible to use in reality... 
I only use some materials in architectural renders of 3D models...
From what I understand, I will need to credit all authors of materials I use in a render, provide links to the source and my renders are all of a sudden under the CC-BY-SA license... (??)
If this is how I should interpret the license, then I need to leave this, as it will means that I can't use any materials in any of the renders I make...
Moreover... If I use a material in a 3D model and share this model with others, I'm not allowed to do so in the future, although the material is only a very small part of the entire 3D model... 
I think this needs further clarification, as it may lead to a completely useless system...
This is also my case but I see things differently.
While we render models based on substances, we are not including substances in our models or modifying them somehow. We are using a converter to produce materials based on the textures a substance generates. Substances in their original form or modified form, that are being included inside a game, are part of that game. A texture that is being generated from a substance is not the substance by itself.
A substance is a generator not the final product we use in our models. If we modify the generator and want to share it, we have to use this CC-BY-SA licencing. That's not what we're doing.
Also the way we sell our renders is completelly different than the way games are sold. We sell one render and that's it. People that sell games must sell several copies of it. I can see how selling several copies of a game is ruined by this sort of licensing, but I cannot see how a single sale is being ruined.
This affects the scenario of making models and textures for selling though but obviously affects the games mass market...
The thing is that I was under the impression that substance was mainly focused on games and not on things like the ones I and Kim create... so this might be hitting your community hard until it's clear enough.
And things are not clear and I bet people will be using the "better be safe than sorry" aproach.
There might even be a chain effect here, that might affect people to a greater extent if companies start suspecting that the materials they are hiring from freelancers that create substances might have been made based on this Licencing format. Ultimately a small freelancer might make this licencing affect all the game...
So I would think this would be very important to clarify to us all.
