Mqtt - bool/num/state... ?

[Humidor]

Hello!
Would need some help please, do not get the point.
Via Blockly I create (publish) a Mqtt Variable on my mqtt.2 Client to a Victron Cerbo Mqtt Broker Device.

whant to have them as number for example

objects are:

I do changes in the VIS:

I subscribe:

I use the in the Victron Cerbo Mqtt Slave Red Node:

If there is a restart of one the values get "null", "true", false".... the Victron Cerbo get confused (but I do think it is not innocent).

I would appreciate some help and tips, thx!

maybe the starting problem is getting "type": "mixed" on the object created out of Blockly?