Steffen 2.0

thank you very much, works perfectly Looks like my Kerbal orbitting round the mun has a Chance of coming home

Hi, I think I don`t understand how refueling works. I have made a test Setup with 2 tanks and 2 Commadmodules connected with 2 Clamp ports. And I simply can`t transver fuel from one tank to another. The fuel crossfeed works, is one empty, the other one ist used. So, do I need any extra parts? Or is "refueling" just adding a full fuel tank to your rocket and it`s impossible to get fuel back into a tank?