I'll need to read through these papers more carefully, but so far they look promising! When you say the code is published on Zenodo, do you mean this webpage: https://zenodo.org/record/3560075#.XsK1KMBOlPY
Yep, that's the one.
There are several papers describing the t-kwant formalism, I'll leave it to the t-kwant authors to name the most relevant source.
Do you have any idea when t-kwant will be released and/or a paper will be published on it?
Thank you for you assistance, John