My FT clone with black o-rings also shipped a few days ago. The spring isn't supposed to carry current. The juice control was meant to be fully open (making solid contact inside) or fully closed (open contact). .
Sorry but there is no way to say it any other way, wrong on both counts. The liquid control functions anywhere in between from open to closed
The spring carries the entire current.
Here is what I get on mine, with juice control open all the way 1.3 ohms, with juice control closed all the way 1.3 ohms.
For sure the spring is more compressed when juice control is open all the way.
And while I only use my liquid control either all the way on or all the way off the option to use it somewhere in the middle does exist. Then one needs to figure out how to keep it in the set position as it turns quite freely.
BTW, I removed my spring prior to posting just to make sure.