Sue:
please don't panic, you'll be OK!
Things always look tougher than they are in reality. Here's an analogy: I am reminded of this every time my husband takes me to the base of a mountain we are going to climb and I swallow hard in "anticipation." After the fact, I realize the incline (read 'learning curve') was not as steep as I imagined it to be from the ground, and viewed from another perspective, it is really a do-able challenge if you are ready for it.
Remember that the CTX cardios are short andintense, or quick and dirty! You will be doing 22 minutes, max 28 mins cardio rather than the 45 mins on cardios from the classics. Cathe goes in intense ("there's no time for downtime"), but it is over before you know it, really. You will be fine.
If you want to rank your new workouts in terms of difficulty to help your learning curve along a gradual fashion, you might take the CTX first, mixed with Cardio Kicks nowand again, and work your way up to Circuit Max which is on a level of toughness (endurance wise) right up there with the Imaxes for many people. remember also, as the previous poster said, you do not have to do Circuit Max as is in the beginning, or in fact, ever at all. It is your workout, and with DVD's you can make it what you want it to be.
For example, you could do half of it one day, then cool down and do some stretching, yoga, finish some more weights work, then finish the second half the next day. Gradually, you can take on more sections until you feel ready to meet the challenge of the whole thing. Alternatively, you can skip all the weights sections, use it as a superb 30 min cardio killer, then do all the weights work at the end, or not at all! There are others who make substitutions: for example I learned a tip from Aquajock and it makes this video into a regular now for me. Instead of doing upper body weights, which I find tires me way too much, I use that time to pick up the barbell and pump out 2 mins of squats, lunges, plie squats, sit and stands, etc, working only the legs. This makes the tape into a complete lower body scorcher!!!
People experience the CTX cardios in terms of perception of difficulty/intensity differently, but I would rank them, from easiest to hardest in the following way:
Kickbox
All STep
10 10 10
Step and Intervals
Power Circuit
Perhaps this will help you to plan your training so that you don't overwhelm yourself and can achiewve slow steady progress.
THese are three of the best Cathe productions you have invested in here, there's enough here to work out with for months. Enjoy making up new routines for yourself. And the upper body work from CTX done all in one is an awesome workout!
Have fun, take a deep breath, tell yourself you can do it (which you can by the way) and leap in!!! The only way to learn is to do it.
Clare