Oh, I LOVE the "Shaken Serger Syndrome!" Will have to try that at work some time. LOL!
I don't think this machine has it, but if it did... tightening the presser foot tension will help get over the bulky seams.
It seems like everything is working except the upper looper. That upper looper should come right up into the lower looper's "shoulder," and have "just enough" wiggle space, so that when you push the front looper, there's a little movement before it hits the lower looper.