I also have a chettgina, and today I started with #4...
And well, it was the same issue as with #2 and #3. From 0 to 1 is a joke, but anything bigger is painful. I just press endure the pain and sooner or later it gets in. Rotating while doing it (screwing yourself) helps a lot in getting it. At the third day on it it's much easier. Active dilation helps a lot, although chett barely mentions it on the website. Getting a copy of Suporn's manual helped a lot.
Today I had been preparing mentally for the insertion pain that would come. I screamed a bit, bit it went in, even if I feel as if somebody had punched me in the intestines and I can't run today. Oddly enough, the second dilation was almost painless. Achieving absolute relaxation, slowly deep breathing abdominally, and my body was literally sucking it in.
PS: Regarding getting stuck at the phrostate... I'm doing what they told me: Bent knees until 4-5 inches are in, and extending my legs before getting to 6-6,5".
PS2: I'm a masochist with high tolerance to pain. Getting 2, 3 and 4 to dull depth took me 5-10 cm the first time.