The MiniHack benchmark is hosted on GitHub and is maintained by its authors.
The manager of the open-source repository can be contacted by the following email: samvelyan [AT] fb [DOT] com.
We expect that new custom MiniHack tasks will be added to the benchmark suite, designed by either the authors of MiniHack, or by members of scientific and gaming communities. We don't have a concrete schedule for updates. The updates will be communicated to users on GitHub.
Yes, instructions on how to contribute to MiniHack are descripted here.
We use GitHub issues to track public bugs. Feel free to open an issue by carefully following instructions for bug reports.