To discuss code, it is best to use the forum.
For things not suitable for the forum, e-mail us at manopttoolbox@gmail.com.
We are happy to receive feedback and bug reports or requests for more features, to discuss the toolbox in general as well as its documentation and to help you use it.
We would also love to know how you use the toolbox, and if you built nice manifold factories, solvers or tools that could benefit others.