Rename is broken for concepts. Users expect it to have the same effect (active the same refactoring) as the Rephrase, but it doesn't.

In a scenario where it is used I can rename a concept with Rephrase the step. Likewise when I have opened the concept in the editor, I can use Rephrase the Open Concept. However, when I Rename it in the Concepts view (or some other view like the Package Explorer), the changes are not propagated properly. (Scenarios and concepts using the concept break, the Concepts view resorts it but doesn't rename it. (Etc.?))

Additionally:

• It doesn't seem possible to create a new concept, one can only extract it.
• It isn't possible to use a concept created from an existing one. I.e. when you copy a concept, paste it under a new name and adapt it, it isn't useable. (Doesn't show up in Concepts view, nor autocomple, and even when you type it correctly yourself in a scenario, Twist maintains it still needs to be created.)
• It isn't possible to extract a single step into a concept. (Workaround: extract two steps, delete one.)
  This is relevant to us, as to us concepts aren't just a bunch of steps for reuse, but also a different layer in the tests. In the scenarios we express business intent, in the concepts the (user) actions needed (like 'press next'), including testing actions ('verify texts') that are not of business value themselves. A functional step may translate into just a single click, but it's still a translation to us.