Just read the manual :-)
You can assign the mod lever
to up to four different patch parameters,
including Cutoff, Resonance, Pitch, Amp
and LFO parameters. Press [Patch]
then [edit] and the [Control] button (next to
the LFO button down on the right of the panel). There you can scroll trough menus
to configure the Pitch bender, the mod wheel
and the aftertouch on each tone of your patch.

Unfortunately, you can't use any of those controllers to modify FX parameters...