Tremolando and Nuages Gris

[Rez]

I'm working on Liszt's Nuages Gris and have some questions on the LH tremolando.   I've seen this technique in many other pieces, so I'd like to get this down correctly.

Is all the movement in forearm rotation?  Should their be any added movement from the fingers?  Should the hand arch be absolutely solid? I think this topic was also addressed in an Octave Tremolo thread, but a few questions still linger for me.  Also, should you accent any notes, say the beginning of a bar etc, or should it just be an even sound, kind of like an alternating pedal tone?