Felt like a positive heading for a change Dima here, the originator of the post.
Well, I now have VISTA and Acrobat9 - bought CS4 a while ago. And alas - the SAME FREAKING PROBLEM as I had on XP and Acrobat 8.
Now, luckily I found my post. Read everyone's feedback, and have some great news:
1. If you read above, you'll find how to merge into an XML file, as opposed to merging into a CSV. I then imported this "merged" XML file into Excel 2007 as data, pressed all the "ok" buttons that came up and A MAGIC TABLE with all data nicely populated appeared! Task complete.
2. To test the other theory, I simply copied my original interactive PDF file that I mailed out to everyone INTO the folder with all the re-named XML replies. Then, when I was selecting the "data files to be merged" I just selected ALL of the files in the folder (Ctrl+A). May be it selected the PDF file as well, not sure. Anyway, I then saved the "report.csv" that was created into this folder also. This made for a messy folder. BUT - it WORKED!!!!!!
It seems the engine for collating the info is working, but Adobe forget to give you some instructions to place original PDF file into the folder with all the XML replies.
Adobe - this could be a simple message when you go to select the XML replies. Good luck with fixing this bug!
Hope this helps others,
A happy Dima Ivanov