kevotheclone, thanks for writing again. However, I think I have resolved my problem. I do not have a thoroughly reasoned conclusion but I am prepared to handle this pragmatically. To be honest, I have not really thought through the idea of a RAM disk as my netbook has limited resources and therefore that is not an option. Anyway, I am not sure that memory speed actually is the issue so much as traffic.
By setting ChannelUpdateAgentConcurrency to 1, so far I appear to have solved the problem as I have not had the delayed write failure since. Support may be right in thinking that part of my flash disk drive is faulty but I think that conclusion may be premature. If as he also says, some flash is sophisticated and well developed but other flash is still in the early stages of development, it is quite possible that what I have is the latter. When I changed the setting to slow throughput during channel updates my reasoning was that Awasu may test my disk to a much greater extent than with other applications, since failure had not happened before or with any other file. If that is the case and it does not happen since the change, that may be the end of the story. Also what I read at support.microsoft.com/kb/330174 makes many suggestions to avoid delayed write failures, so it cannot always be a hardware fault so much as a limitation. All I need to do is back up more frequently as a precaution in case it happens again and with more serious consequences. If it does I will consider if a failure is the cause and another work around such as MS suggest too risky. I believe if that were to happen, I would have to make at best an educated guess and prepare for the possibility of getting it wrong. I am reconciled to that and, since I have another PC, would cope.
Backup for me is a doddle because I keep all of my data files in a tree structure under a single folder on both my PCs. Therefore to backup onto a portable HDD all I have to do is drag and drop the parent folder. I do not bother with incremental backups any more or zipping files because I do not have enough data relative to space on my backup drive for efficient use of that space to be a consideration. Besides, when occasionally I want to get to an older version of a file from my backup, this arrangement makes for far greater convenience.
PS If you liked ExEclipse, I hope you like PartialEclipse now it is in the Wiki. I had no idea how to put files there but Support liked it too and put it there for me. Better name which I asked him to change it to. No other differences!