Fountain particles direction not functioning?

I’m testing the Forces of Nature/Volcano/Fountain effect. I’ve created a custom sprite, and everything works fine except for the fact that I can’t change the angle/direction of the particles. It only goes straight up, and any changes on the initial key frame don’t seem to work. Is there something I’m missing or does this just not work with this specific effect?

EDIT: I’ve found that I can merely rotate the whole effect with a peg, but the physics don’t work out as the particle generator still behaves as if it were pointing upward. Particles towards the direction of the tilt don’t fall as much as they should and those on the other side actually fall upwards and back.