Tim - I was on when you were on, but I must have gone on to another Forum.
Chunyi Lin says to continue the practice in spite of itching, tingling, and stinging. That is the energy moving. Allow it to move and do its thing.
The first few times I did Small Universe I got sick to my stomach and couldn't go on. Chunyi said to keep doing it until I threw up. Well, I never threw up, but another a couple of additional 30-minute sessions the sensations went away. Now it is one of my favorites.
Chunyi says the Seven Steps to New Health is great for the lower extremities.
Chunyi says to do the sitting meditations right away. If you have physical problems you should practice the Active Exercise 75% of the time. Balance out your practice with Sitting Meditation.
As you become healthier, increase the amount of Sitting Meditation.