set_switch() not working on gen5 (Model ZW075-C16)

[Cherrier Sylvain]

Hi,
I have a problem with my switch gen5 (Model ZW075-C16).
it works with z-way-server, i can switch it off and on.

the switch is identified in python_openzwave
(my raspberry shield is id 1, my switch is id 6)

I have a variable my_nw which is a ZWaveNetwork, and it works.
if i do

my_nw.nodes[6].get_switches() i get an int (72057594143391744)

with the previous versions, i did this to switch it on

my_nw.nodes[6].set_switch(72057594143391744, True)

It is no more working with version 4.x
the state value is always false, even if i try to set it to true (with set_switch() )

my_nw.nodes[6].get_switch_state(72057594143391744) gives always False

when i try to get all possible value, i get None

my_nw.nodes[6].get_switch_all_items(72057594143391744) gives None

 I wonder if i keep the link with my object... As if i have the connection at the beginning, but then no refresh at all... no communication..
My first question is

Am i doing it the correct way ?