Sharona,
When I started with Cathe (not too long ago), I also went right from Basic Step/Body Fusion to Imax 2. I found Imax 2 much more challenging than Basic Step/Body Fusion, and I had to work up to it, by doing intervals 1-5 only or 6-10 only, as other suggest. I remember feeling discouraged, because I found Imax 2 so much harder than Basic Step/Body Fusion, but it IS a more advanced workout, and you just need to work up to it. I think the suggestion of starting with a 4" step is a great one, too. You'll get it soon enough, and then you'll really enjoy it. Just keep plugging away! Good luck!