Since the top thread is not being caught and held by the bottom thread, it is definitely a bobbin issue! Take everything apart in the bobbin case one more time. Also be sure you are putting the bobbin in with the thread feeding off in the correct direction. (On my Ellisimo, I hold the bobbin up and have the thread coming off the left side where it looks like a "P".)
After you have threaded everything top and bottom again, leave the bobbin cover off and hold the top thread in your hand while turning the hand wheel. Watch to see if the top thread is being caught by the bobbin thread as it goes around. If it is not, then it sounds like a timing issue.
This is just my opinion of course. I take older machines apart and service a lot of machines for friends. However, I don't mess with the computerized machines other than minimal issues.
Good luck and hope you get this resolved so you can sew! (Perhaps a cheap older backup is in your future???)