Teltonika GH4000

Good morning Gurtam users (or good evening for the Down Unders )

We begins to work with the GH 4000 of Teltonika.
Got 3 very important questions :

- First : The device send "Param240" which is not indicated in the user guide neither in the device page in the Gurtam website.
This parameter sometimes turn "Param240=0" and other times turns  "Param240=1" (see the attached pic).
Is anyone of you could indicate how I am supposed to translate this Param240 please ?

- Second : Is one of you have already set the "priority sensor" ?
The priority sensor has 4 positions :
0 = Low
1 = High
2 = Panic
3 = Security
I guess that we do have to create a calcul table in the sensor page, I try but I don't know where I have to indicate "Low", "High" etc...
I just need to localize the 4 params in Wialon Hosting monitoring because as you can see in the pic attached, sometimes the priority is 1 and others times is 2.

- Third : Our customer doesn't need tracking, he just want to know the position of the worker when he arrive in the dockyard.
The worker should be able to send a position by himself with the device, and only a position when he arrive and when he leaves.
But it seems that we do not set properly the GH because this funct doesn't work.
Is someone of you have already work with that ?

Thank you for your attention and for your replies,

Have a nice day
Xavier