Problem Xrock 433mhz USB

Hi everyone,

i used a X-Rock USB 433 Mhz TX/RX module for Mavlink work good, two days ago i want increase performance of latency, and i see Ardupilot manual and change
SETUP/OPTIONAL HARDWARE/SIK RADIO. set for LOW LATENCY.

But burn a big problem, the Ground module have to MAX_WINDOW 131 and
the remote module have MAX_WINDOW 33 and now is not possible to connect.

now the problem is: Ground module have USB but Remote Module not have any port and i can’t change on remote module any parameter because not are connect.
I have try with Mission Planner SIK Radio menu and also with SikRadio Setup tool but
i can’t resolve.

the remote module have 4 wire
GND
+5V
RX
TX

you think is possible to connect to 9pin RS323 port and try to change parameter??
other ideas ???
thanks
Fabio