I'm glad that you got it to not skip stitches. When I first saw this thread and the picture, it seemed to me that the pressure regulator seemed a little higher than it should be. I have been known to reduce or release the pressure regulator when storing the machine and forgetting that is what I did.
Of course, it doesn't feed fabric and frequently doesn't even make stitches.
Janey - Neat people never make the exciting discoveries I do.