Generation encounters missing file

[MarkDBlackwell]

While generating two branches (in this way):

Git branch for the prelaunch app?
          2)  master
Git branch for the main app?
          2)  wip (work-in-progress)

Rails Composer emits a message:

prelaunch  Unable to obtain features/users/sign_up.feature from the repo https://raw.github.com/RailsApps/rails-prelaunch-signup/master/

Currently, the file does not exist in that directory.

Furthermore, Rails Composer does not halt—but should it, in this kind of case?