I have the same problem with the course accessibility.
Yesterday I could access to color fundamental course in concept flow, but not today, it just completely gone and direct me to homepage instead.
Also, I reported some bugs/glitches in the bottom right conver button, but no response..
Thanks for the heads up folks! I'll get those quizzes fixed right away, not sure how that happened.
Second, the rigging course is still part of the Intro to Blender learning flow, it's just in section two for now: https://cgcookie.com/flow/introduction-to-blender
The Color Course is there as well, does clicking on it still take you to the homepage? That should be fixed now: https://cgcookie.com/flow/introduction-to-digital-art
If you see anything else, please feel free to report it in the Intercom chat in the bottom right. There are a lot of conversations to dig through at the moment but we will absolutely reply to them all as soon as we can.