Just received an answer from the FFG support:

A figure cannot perform an action while moving through another figure.

Thanks,
Justin Kemppainen
Assistant Board Game Manager
Fantasy Flight Games

Cool, thats' the only logical answer.

Question: if I want to move over a large hostile figure, can I spend my 2 actions as moves to get 2x my move points and spend them as if coming from a unique pool? Ex: to pass over 3 hostile squares with 4MP/move even if the move points from my 1st action are exhausted while moving over the figure?

Yes, to actually move a model is not an action. The action is to buy movement points, yeah, its a bit weird.

When you say moving through do you mean you move one space into an adjacent figures square then attempt to Attack from that square?

Yes. It could also be said:

A figure cannot perform an action while (temporarily) in the same square as another figure (when moving through).

@Tauntaun As I read it, yes. You'd be 'using' both your actions before moving to get the points, then spending those points.