If you're learning the Tibetans, you start with three repetitions of each move, and only add one or two repetitions per week until you're up to 21 reps. If you need to do them slowly, they might require more strength, and that might mean you'd add more repetitions more gradually.
I don't know whether your concern with spinning is related to dizziness. If so, I'll note that I've got some evidence that Feldenkrais' theory that dizziness is caused by holding one's breath has something going for it, and the Tibetans are a good way to work on breathing while turning.
The fourth involves keeping your head level with the ground. T5T offers leaving your head vertical through the move as an option, or leaving your head and shoulders on the ground.
The fifth does involve having your head at about a 45 degree angle facing down, but not dangling.
You can do the movements slowly and get the benefits from them.
An exercise:
Name something that you do not do but should/wish you did/are told you ought, or that you do less than is normally recommended. (For instance, "exercise" or "eat vegetables".)
Make an exhaustive list of your sufficient conditions for avoiding this thing. (If you suspect that your list may be non-exhaustive, mention that in your comment.)
Precommit that: If someone comes up with a way to do the thing which doesn't have any of your listed problems, you will at least try it. It counts if you come up with this response yourself upon making your list.
(Based on: Is That Your True Rejection?)
Edit to add: Kindly stick to the spirit of the exercise; if you have no advice in line with the exercise, this is not the place to offer it. Do not drift into confrontational or abusive demands that people adjust their restrictions to suit your cached suggestion, and do not offer unsolicited other-optimizing.
To alleviate crowding, Armok_GoB has created a second thread for this challenge.