Oblique Frustrum Camera (horizontal X, vertical Z)

Hello!

I am trying to make a simple (?) oblique orthographic camera, where the Z-axis is shown vertical, the X-axis horizontally and the Y-axis diagonally (like a 30 degrees angle).

I've found this: https://github.com/keijiro/unity-oblique-projection which shows: https://raw.githubusercontent.com/keijiro/unity-oblique-projection/gh-pages/screenshot.png

And this is exactly what I am looking for, however I cannot get the Z-axis vertical, nor can I get ray hit detection to work with these scripts. (There's simply never a hit, as if the ScreenPointToRay for this oblique camera doesn't fire in the correct direction).

Anyone got any experience with making such a camera?