I don't have any leakage but others might. I ordered from Intaste and it comes with a small screwdriver. One end is flat head and the other end is Philips screw. Both has a small o-ring. Use one of them for the fill screw and it should solve your leaking problem
Brilliant! I just put that oring in and it's the perfect size. You have a great eye for detail. I didn't even notice the orings on that screwdrivers.
Let's see how it works.