Hey Alex. Glad you liked it. Yeah the Tagleharpa is midi. Same with the frame drums and other bigger percussions. Although for the Tagleharpa it is already planned to get a real one this year and I'm in contact with a luthier from Poland to build one^^.
There are some more details like Lyrics and used VSTs and instruments on the main project page. But we'r also more than happy to share some insights of how the song was made ;-)