If you have any questions, please create an issue. When an issue is opened, course staffs will mark the issue with an appropriate label based on its contents.
When describing your problem, it is always a good idea to use Markdown references to pinpoint your commit and line numbers (if you are dealing with public repository). See http://stackoverflow.com/questions/23821235/how-to-link-to-specific-line-number-on-github for more information.
Please search for the previous questions. You can search all issues including closed ones in GitHub. Also, try Google search as well. Often time, you will be able to find the answer easily from Google. Create an issue only when you cannot find any relevant questions. We will deduct point(s) if you create a duplicated issue.