Differential Unit problems of the 2009 Subaru Forester

I was driving to work, and the car wouldn't accelerate, it also handled roughly. The check engine light, cruise control light was flashing, along with vehicle dynamics control warning light. I had my car towed, as it wasn't drivable. My local garage repaired my car, I received 4 new spark plugs, and an air filter. 9 days later the check engine light came on, as well as the cruise control light, and the vehicle dynamics warning light, again it was repaired, this had to do with the catalytic converter message, but all my local garage could find was a small leak near the manifold that they repaired. 2 days later the check engine light went on again, I now called my Subaru dealership, they replaced a faulty catalyst converter, and af sensor, the also changed my oil, as it was due, and suggested I have a transmission fluid flush and refill, and that my rear and front differentials, needed a drain and refill. 5 days passed another check engine light, this time it was flashing, I had to have my car towed, the Subaru dealership discovered the wrong spark plugs were put in initially, and replaced them with platinum tip spark plugs that my model takes. 4 days passed another check engine light, with being unable to accelerate, I was going up hill, so I continued on, to reach a parking lot, I could stop in but suddenly, it felt like something unblocked, this made the check engine light go away, until 2 days later, another check engine light, I once again brought my car back to the dealership, the mentioned something about the catalyst converter, but said it was 'too soon" so they left the work order open , in case it occurred again,and gave me this lecture about the grade of gas I am buying. 4 days later the check engine light returned, this time Subaru discovered the my other O2 sensor was faulty, and they would replace it, when the part comes in.