Firstly I want to thank you all for your help.
All the comments are helpful as it is a steep learning curve for a begginer.
I am cheesing in isolation here in my corner of Yorkshire, UK, and don't know anyone who has any cheese making experience so it is very supportive to have such a link to your wealth of experience.
Answering a few questions which have come up in your posts.
The cheese middle does not in reality have any pink hue to it, it is a healthy looking creamy colour, any pinkyness must just be the camera not giving a true picture.
The smell has a bit of an ammonia tinge, but in mostly an unpleasant 'don't think that can be right' nasty smell.
The PC might be under suspicion of not being fresh enough.
I have had a blue cheese going too - which I am pleased to say is a big sucess (a little too dried out but still very yummy to eat, I think next time it needs higher humidity, and its holes next time need to be more in size and quantity - but that is a whole other topic!)
but the green staining on the brie is nothing like Penicillium Roqufortii, it is a yellow/green fluorescent sheen, in patches. On another thread I found, using the search facility, someone mentioned fusilium or something as a contaminant looking similar?
I think I am probably being a bit too ambitious trying such a challenging cheese this early in my cheese career! But up to now everything has been a sucess and so I was lulled into a false sense of confidence and being a 'stinky' cheese lover you can only eat so much cottage cheese before you NEED to go for some character
built cheese!
I am looking forward to reading through some of the older threads, especially those some of you have pointed me at, which look very helpful, interesting and educational, to help me improve my knowledge and understanding of the art. It is quite tricky as a beginner to know which elements of the process are critical and which can have a bit of tolerance. I have already 'broken' 2 hygrometers which I don't think could cope with the high humidity! which seems a bit daft as that is their raison d'etre!
I hope there are not too many 'lost in translation' issues for you US guys with my English English! I have to admit some of the stuff I am reading on the forums goes over my head rather - 'what's that all about' - as I think they must be Americanisms?! (Something about violins left me totally bemused?!)
So back to the brie. The remaining 8 inch one is certainly getting worse not better, and so I think it is probably a write-off. But it is encouraging to read in one of the posts I am directed to in your replies that someone says you need to have a few goes at a cam (presumably camembert) before you get the hang. So next cheese will probably be something a little less challenging, but I will have another go later at another brie as it is a favourite.