Hello Richard Lewis 20814,
If your Expression Studio purchase came in the standard Microsoft clear plastic curved clamshell (as in this pic:
http://www.amazon.com/gp/product/images/B0013IRKB0/sr=1-1/qid=1240663151/ref=dp_image_0?ie=UTF8&n=229534&s=software&qid=1240663151&sr=1-1 ) then the Product Key is of course printed on a yellow-orange stiicker inside the clamshell and if the product were not opened before purchase, the Product Key label should not be defaced at all, so you should be able to read the PK to install, activate (and if applicable, validate) the program.
As predictable an answer as this is, IMHO your best option is to return the software package to the Seller for an exchange. Personally if I spent about $650 for a software package, I would want the Certificate of Authenticity to not be defaced in any way, just in case there was a problem later on regarding a question as to the genuineness of the product. If a situation arose where you lost the Product Key (maybe the label falls off or gets defaced), in order to request a new PK from Microsoft, you would need to provide them with all of the numbers printed on the CoA to prove the validity of the product and to get a replacement PK, so while those numbers are not critical now, they could become critical under future circumstances. Perhaps sending a nice clear digital snapshot to the seller showing the accidental defacement of the CoA by their mistake of taping the receipt to it would help to convince them to make the replacement with no shipping charges either way :-)
On retail packages, the various numbers printed on the external CoA are completely different from the Product Key.
You may find your answer about ExpressionWeb Blend at the dedicated website here:
http://expression.microsoft.com/en-us/default.aspx
For great advice on all topics XP, visit http://www.annoyances.org/exec/forum/winxp