Looking at the first set of questions, here are the answers for the current legislation.
1) Do you know how long it takes to get a UK passport for baby while we are still in the UK?
7 working days through the Passport Office. Your child will be issued a 5 year passport. Please provide a certified copy of your childs birth certificate
2) Can I apply for a SA temporary resident (spouse) visa and a permanent resident (spouse) visa at the same time from the UK?
Once you have been married for longer than 5 years, you are able to apply for permanent residency. Yes, you can make both applications through the South African High commission in London. The permanent residency application will be referred to Pretoria and take over 12months to issue. I suggest applying for your temporary residency permit first in London, then submitting your permanent residency permit once you have arrived.
3) Can I apply for a temporary visa once we are married for 5 years?
You can apply for it the moment you get married, so yes.
4) Can I move to South Africa on the temporary visa and then receive the permanent visa while I am in South Africa?
Please see answer 2
5) If I cant apply for a temporary visa can I move to South Africa on a tourist visa while waiting for the permanent visa to come through.
Please see answer 2
6) How long after receiving the temporary and/or permanent visa do I have to arrive in South Africa?
There is no written rule, but we suggest no later than 90 days from issuance.
7) Can our child travel with us to South Africa on the UK passport before we have them registered in South Africa?
if you have not been able to get a South African passport issued for your child on the basis of its father being South Africa, then your child would also apply for a temporary residency permit on the basis of being a dependent
8) Will the baby require a visa? Or are they automatically allowed through my husband's citizenship or my spouse visa to come with us?
please see answer 7
9) Can I apply for South African citizenship for baby while in UK and finish it in South Africa if we have to move before it is finalised? (Is it based to start this process in the UK or wait until South Africa).
You need to finish a process in the country in which the process began. So no, you would need to get the South African passport for your child before you leave. I am not sure how long this process takes. I estimate 9 weeks.
10) In the UK who do I need to contact to do all these things!
No idea in the UK, and on this forum I may not advertise for SA either. They are very strict on no advertising, but I'm sure I am allowed to say that you can search in Google and should come right. The only advice is that you should use immigration lawyers only.
I hope this helps all of you with the same questions.