Hmmm, I wonder if this means that there’s some kind of timeout error for Shiny. Could you open an issue in jupyter/repo2docker with this error? I wonder if we need to bump up a configuration value somewhere…
There are a number of differences with your attempt and the example.
The example uses installation of shinydashboard and as discussed here the example uses the two-file approach for shiny apps where you need a server.R and ui.R file in a directory.
Before opening an issue I’d run the repo locally with http://repo2docker.readthedocs.io/en/latest/ and take a look at the logs to see what you can see. This will also be the first question asked on the repo2docker issue tracker