If you're using Mac OS 10.5, you can open the CS4 file in Preview, and save it as a PDF from Preview, which "should" open in CS2. Can't guarantee results if it's a complex file with layers & transparency, but this move has saved my hide a couple times.
Maybe get the client to send a jpeg preview so you can make sure it hasn't gotten garbled.
There is no reason the CS 4 file cannot be opened in CS 2 or placed in an empty CS 2 Document.
I can do the convertion for you but the file you uploaded its damaged or somethig.
Could you please reload the orignal Ai CS4 file?
may be on a server like www.mediafire.com because on this forum could be a problem.
I have CS3 and quite often I get CS4 files that cannot be placed into a CS3 document. When you save the resulting file it will be blank...same thing happens when I place a CS4 file into ID (which looks fine) then when I export it to eps the resulting eps file will be blank in CS3. So this work around doesn't always work.
The only work around I have found is to open the file with Acrobat (9 Pro), and then save as an eps file.
Repost the file, but ZIPped, and with no spaces in the filename.