@mfalkvidd
Thank you so much :D Finnaly it is working as it should do!

#define MY_DEBUG 
#define MY_RS485
#define MY_RS485_DE_PIN 2
#define MY_RS485_BAUD_RATE 19200
#define MY_RS485_HWSERIAL Serial
#define MY_NODE_ID 3

#include <AltSoftSerial.h>
#include <SPI.h>
#include <MySensors.h>  

AltSoftSerial altSerial;

int msg[1];
const uint64_t pipe = 0xE8E8F0F0E1LL;

const int requestPin =  4;         
char input; // incoming serial data (byte)
bool readnextLine = false;
#define BUFSIZE 500
#define CHILD_ID_WATT 0
#define CHILD_ID_KWH_LOW 1
#define CHILD_ID_KWH_HIGH 2
#define CHILD_ID_GAS 3
#define CHILD_ID_CURRENT 4

char buffer[BUFSIZE]; //Buffer for serial data to find \n .
int bufpos = 0;
long mEVLT = 0; //Meter reading Electrics - consumption low tariff
long mEVHT = 0; //Meter reading Electrics - consumption high tariff
long mEAV = 0;  //Meter reading Electrics - Actual consumption
long mEAT = 0;  //Meter reading Electrics - Actual generated electricity (Solar panels)
long mG = 0;   //Meter reading Gas


MyMessage msgWatt(CHILD_ID_WATT, V_WATT);
MyMessage msgKwhLow(CHILD_ID_KWH_LOW, V_KWH);      //Was V_KWH
MyMessage msgKwhHigh(CHILD_ID_KWH_HIGH, V_KWH);     //Was V_KWH
MyMessage msgGas(CHILD_ID_GAS, V_VOLUME);



void setup() {
//  Serial.begin(19200);
//  delay(1000);
  
  altSerial.begin(9600);
  delay(1000);
}


void presentation() {
  // Send the sketch version information to the gateway and Controller
  sendSketchInfo("Node", "1.0");
  present(CHILD_ID_WATT, S_POWER);
  present(CHILD_ID_KWH_LOW, S_POWER);
  present(CHILD_ID_KWH_HIGH, S_POWER);
  present(CHILD_ID_GAS, S_GAS);
}



void loop() {
  long tl = 0;
  long tld =0;
  if (altSerial.available()) {
      char input = altSerial.read();
      buffer[bufpos] = input&127;
      bufpos++;
      if (input == '\n') { // We received a new line (data up to \n)
        // 1-0:1.8.2 = Electricity consumption high tariff (DSMR v4.0)

        
        if (sscanf(buffer,"1-0:1.8.2(%ld.%ld" , &tl, &tld) >0 ) {
          tl *= 1000;
          tl += tld;
          mEVHT = tl;
          //mEVHT = tl * 1000 + tld;
          if (mEVHT > 0) {
  
            //mEVHT = 0;
          }
        }
  
  

        if (sscanf(buffer,"1-0:1.8.1(%ld.%ld" ,&tl, &tld)==2){
          tl *= 1000;
          tl += tld;
          mEVLT = tl;
  
          if (mEVLT > 0) {
  
  
          }
        }


  
        // 1-0:1.7.0 = Electricity consumption actual usage (DSMR v4.0)
        if (sscanf(buffer,"1-0:1.7.0(%ld.%ld" ,&tl , &tld) == 2)
        { 
          mEAV = (tl*1000)+tld*10;            
          if (mEAV > 0) {
  
          }
        }




//Gastand uitlezen

if (sscanf(buffer,"(%ld.%ld" , &tl, &tld)==2 ) 
      {   mG = (tl*1000.0)+tld;
      mG = mG;
      }




  
        // Empty buffer again (whole array)
        for (int i=0; i<500; i++)
        { 
          buffer[i] = 0;
        }
        bufpos = 0;
  
      }
       
      if (input == '!') {   //uitroepteken geeft einde van telegram aan, dus we gaan data versturen
        #ifdef DEBUG
          printData();
        #endif
        send(msgWatt.set(mEAV));
        send(msgKwhLow.set(mEVLT / 1000.0, 3)); 
        send(msgKwhHigh.set(mEVHT / 1000.0, 3));
        send(msgGas.set(mG / 1000.0, 3));
        mEVHT=0;
        mEVLT = 0;
        mEAV = 0;
        mG = 0;
        //client.stop();
      } //Einde vraagteken detectie   
  
    } 

}


 

And here an picture how it is showing up in domoticz:

I guess i found it now,
Looks like that V_LEVEL and V_LIGHT_LEVEL are both not behaving as expected,
I have changed these now to V_TEXT after that the sensors was finaly working within domoticz.

Also i had some cabeling issues, looks like the sensor doesnt like an cable length off 2 meter on 4x 0,44mm2 wire..
Tommorow i am going to place the arduino closer to the weather station and i guess everything would be fine again then !

Here my latest sketch:

#define MY_DEBUG
#define MY_RS485
#define MY_RS485_DE_PIN 2
#define MY_RS485_BAUD_RATE 19200
#define MY_RS485_HWSERIAL Serial
#define MY_NODE_ID 5


#include <MySensors.h>  
#include <BH1750.h>
#include <Wire.h>

#define CHILD_ID_LIGHT 25
unsigned long SLEEP_TIME = 25000; // Sleep time between reads (in milliseconds)

BH1750 lightSensor;

// V_LIGHT_LEVEL should only be used for uncalibrated light level 0-100%.
// If your controller supports the new V_LEVEL variable, use this instead for
// transmitting LUX light level.
// MyMessage msg(CHILD_ID_LIGHT, V_LIGHT_LEVEL);
MyMessage msg(CHILD_ID_LIGHT, V_TEXT);  
uint16_t lastlux;

void setup()  
{ 
  lightSensor.begin();
}

void presentation()  {
  // Send the sketch version information to the gateway and Controller
  sendSketchInfo("Node 5", "1.0");

  // Register all sensors to gateway (they will be created as child devices)
  present(CHILD_ID_LIGHT, S_BINARY);
}

void loop()      
{     
  uint16_t lux = lightSensor.readLightLevel();// Get Lux value
 // Serial.println(lux);
 // if (lux != lastlux) {
      send(msg.set(lux));
     // lastlux = lux;
 // }

  wait(SLEEP_TIME);
}

@Nca78
Thanks for your help !