You're correct, you need to loosen the screw you pointed to. A good test is the one you were doing, called the "drop test". Pull out a length of thread and drop your hand quickly. The bobbin case should slide down the thread and expose 1-2". You want very little tension on the bobbin thread. If you're having to yank on the thread to get it to come out it's way too tight. I believe the proper tension is like 40g. Goodluck and don't be afraid to play around with the adjustments, it's the best way to learn.
I have the same problem. Did you ever get it fixed?
You're correct, you need to loosen the screw you pointed to. A good test is the one you were doing, called the "drop test". Pull out a length of thread and drop your hand quickly. The bobbin case should slide down the thread and expose 1-2". You want very little tension on the bobbin thread. If you're having to yank on the thread to get it to come out it's way too tight. I believe the proper tension is like 40g. Goodluck and don't be afraid to play around with the adjustments, it's the best way to learn.
22-23 grams according to The Featherweight Shop