Are you mixing up your training, and making yourself unpredictable enough? Are you raising the bar enough for him? He sounds a bit bored to me (maybe you too...).
Why are you stuck at Level 1 (sorry I know nothing about World Cynosport-- is that the on lead part like AKC novice?)? What do you need to do to get to Level 2? If it's a matter of offlead work, then yes, you most certainly have holes in the training if he's not heeling w/ you as he did before. Why don't you use the trainer with the methods that worked years ago anymore or is this a matter of that trainer not doing Rally? Anne