That's what it was, I needed to set a group (default). It worked with my Monument IDs as names too :
{
"Name": "Missile Silo",
"Radius": 100.0,
"Radiation": 0.0,
"Comfort": 0.0,
"Temperature": 0.0,
"SafeZone": false,
"Location": "-49.56011 43.35525 811.358",
"Size": "0 0 0",
"Rotation": "0 0 0",
"Id": "nuclear_missile_Silo",
"ParentID": null,
"EnterMessage": "",
"LeaveMessage": "",
"Permission": null,
"EjectSpawns": null,
"Enabled": true,
"Flags": "AutoLights"
},
Thank you!