I’m very happy of this mix, as an early MyPaint adopter. Thank you for this great work :).
I managed to compile it on Arch Linux, and made an AUR package, called pencil2d-mypaint-git, to allow other user to take benefits of it too, testing it and perhaps add some returns on problems.
It works really fine, there is only a bug, brushes disappear often, need to restart Pencil2D to see them again. (Edit: I understood, other tool was selected, I don’t know how)