Hi there - from looking at the package source code it seems that a slightly non-standard spherical coordinate system is being used. If you are used to r, theta0, phi0 (where theta0 is the angle between the cartesian vector and the positive z axis, and phi0 is the rotation around the z axis) then you can map from the package output to this system with theta0 = pi/2 - phi and phi0 = theta (or you could write your own cartesian to spherical conversion function, its just a few lines of code).
But I think the answer to your question seems to be no - I couldn’t see a transformation function in this package that does exactly what you want.