Animate a lattice?

something as simple as animating lattice points used to be a snap in Si3d, but in xsi I just dont know were to apply keys to selected groups of points that i want to animate, I can animate the position of the whole lattice but can't figure out how to animate selected points . PLEASE help. I'm sure this is a silly question and i'm doing something wrong, but I'm in the middle of a proyect and can't figure out how to do it, thanks in advance

I'm not sure if this is right, but have you tried saving shape keys? I was doing this for a fluid i had constrained in a lattice; tagging points moving them out and then selecting the whole lattice and saving shape keys. Animate Menu => Deform => Shape => save shape key. I think if you store them , you can reuse them in animation mixer (but with this i have had no experience). Worked for me; hope it works for you

Thank you so much baby softy, I don`t know if thats the right way to animate lattices now, but it sure works perfecttly, I could finnaly get to animate those points with your method, thanks again for your BIGGG help. : )