In medium saucepan, heat spaghetti sauce, mushrooms, seasoning and meatballs over medium heat for 10 minutes.
Scoop out meatballs with a spoon (slotted, if you have it) and place on a plate. Cut each meatball in half. Set aside.
Remove sauce from the heat.
In medium bowl, combine cottage cheese and Italian cheese blend.
Spray the inside of the crockpot bowl with non-stick spray.
Place 1/4 of the sauce in bottom of crockpot.
Place one layer of uncooked lasagna noodles over the sauce, breaking them if necessary.
Spread 1/2 of the cheese mixture on top of the noodles.
Drizzle 1/3 of the remaining sauce.
Repeat the layering of noodles, remaining cheese mix, remaining meatballs and 1/2 of remaining sauce.
Lay down another layer of noodles, and spread with the remaining sauce.
Cover, cook on high for 1 hour. Reduce heat to low and cook covered for an additional 3 hours or until noodles are soft.
Sprinkle mozzarella cheese on top. Replace lid and cook on low for an additional hour, or until cheese melts.