Thanks to everyone who gave me advice on how to manage. Can't sleep so thought I'd give you an outline of what it was like. Rather a long rant I'm afraid.
Couldn't find the blue badge parking but a helpful man let us park in the season ticket holders car park.
Got inside and was eventually directed up in the lift to the disabled viewing area on the balcony next to where all the private, expensive parties are. Given two chairs from the outdoor bar. So far so good as we had good views of the race course and stage.
I was told to go downstairs to the toilet but disabled one shut because floor wet as had only just been cleaned and the other one was on the other side of the very busy foyer. So went outside to the one with the RADAR key which turned out to be full of rubbish! So I found a supervisor who came back upstairs with me and showed me the one on the first floor which I was apparently allowed to use, although I got suspicious looks from the security desk.
Then we were told that we weren't supposed to be using the chairs because we were a fire hazard being in the area near the steps which were the fire escape. Wheelchair users can sit but carers have to stand - 3-4 hrs if watching races and concert. They obviously didn't know what to do with someone who can walk with aids but can't stand. We argued the toss and kept the chairs until the concert started but when we had to move because some prat from security deliberately stood in front of us hubby's chair was taken away and I think they would have happily taken mine too, except they didn't know what to do with me because I wasn't sitting in a wheelchair!!
We were in the most exposed part of the grandstand and it was freezing cold and the acoustics were hopeless so we left before the end.
The tickets were very expensive and yet we were treated like second class citizens in a very well known racecourse I will email them later on with a few choice comments!