nat

thanks again i found the problem, it was IFS, cheers

Could it be Interstellar Fuel Switch that's creating the problem. Simple construction requires IFS though.

Im using the orbitaldock and I'm having the same problem with the simple construction mod. I click release and the new rocket doesn't have any fuel. I'm launching from a space station with cross feed enabled btw and thanks for the lightning fast answer.

Sorry if this problem was already answered but everything seems to work fine with the mod except when i finalize build (even with the sliders for xenon or whatever fuel at max and with lot's of rocketparts and full fuel tanks) my newly made rocket doesn't transfer on any fuel and has empty fuel tanks. Solid fuel and batteries seem fine but fuel transfer is an issue. Did I install something wrong?