Hi Kaxelcy,
Thanks very much for your questions and congratulations on your offer!
So I've spoken with a colleague in the postgraduate admissions team to try and get some more information on your questions, so I'll try and answer them as best I can!
1. In terms of compulsory modules, apart from the research methods modules offered by the Graduate School which you should attend, there are not really any 'compulsory' taught modules as the programme you have applied for is 100% research. However, with the agreement of your PhD supervisor, you might be able to sit on other modules but you wouldn't be required to.
2. Its hard to say exactly how much time a Postgraduate Research student would need to be on campus in the first year, it would really depend on what you and your PhD supervisor agree is necessary. Therefore it could just be for a few hours a week or a lot more, depending on whether you want to travel to campus to use the library and other facilities. So, in terms of choosing accommodation, it may not be necessary to live really centrally if you are only needing to travel in once or twice a week.
3. In terms of off-campus fieldwork, I'm afraid you wouldn't see a reduction in tuition fees as this is at a set level for the programme. Obviously in terms of living expenses, if you aren't living in London (paying rent, travel etc) then you would see a reduction in living expenses in the nine months out of the country.
4. You're right, there are a number of funding opportunities available for Postgraduate Research students. If you haven't submitted your applications for funding yet, please make sure you do so as soon as possible. You can find more information about applying for PG funding here
http://www.kcl.ac.uk/study/pg/funding/sources/index.aspx and the Graduate School also has a lot of useful information and contact details:
http://www.kcl.ac.uk/study/pg/school/index.aspx. In terms of the basis of why one application is approved for funding over another, well, that's really down to the discretion of those reading the applications! Essentially, if they think the research is really valuable and progressive then it would be more likely to be approved.
5. It is possible for you to transfer to part time study in your third year (or before) and you are right, part time is roughly equivalent to two years of study. So if you transfer to part time in year three then that would mean you would be studying for a minimum of four years in total. Just one thing to mention, if you require a visa to studying in the UK and you secure it on the basis that you will be studying full time then that may cause a problem if you are thinking of transferring to part time, so that would be something to think about when considering the option. I'm afraid, you would need to look into the visa as I'm not able to advise you on that I'm afraid.
I hope this helps!
Fran