Hi, I had the same experience as you, i did a dip he and qualified in 1995, 16 years ago, i have taken various courses including my non medical prescribing. I commenced my application to the CNO in 2010, they have also made me jump through hoops, i had references and job descriptions from all the places i'd worked over the 16 years, fortunately i knew how to contact people and was on good terms with all. I took their bacculareate equivilency essays, i got transcripts, certificates etc from the ukcc and universities and it took until December 2011 for them to finally let me take the exam. The uni had sent transcrpts with hours of study and clinical hours but unfortunately could not give the CNO theoretical and course content as they did not have acssess to the information any longer, they had lost it. The uni sent them a letter from the course director saying this is all the information they posses and do not hold any more info. The CNO wrote back 6 months later asking for more information!!
They want all the information you can physically get hold of it doesn't matter how much experience you have, they are trying to decide wether your training is equivilent to theirs, it is very frustrating as we clearly have a lot of experience under our belts and are far more knowledgable than a new grad, but they will not get past this. In the end the university to wrote a letter stating that they do not hold or cannot provide any more information they also sent a copy of the confirmation that i had passed the course, (i don't know why they could'nt accept the 1st letter) this seemed to do the trick, i have decide to sit the exam in June 2012 to give me plenty of time to study.
Also for your information, it is not the CNO that you send your information to that make the decision your case manager sends the information to be assessed externally, keep on top of your case manager because you want to make sure you do not go to the bottom of the pile each time you send more information in, i contacted mine regularly to get progress reports, i know they have many cases to deal with but on this occassion you have to be selfish. Your case doesn't seem too different to mine so hopefully you will get to write, and hopefully it doesn't take them as long to decide. If you need any more info feel free to ask.