When installing from the rescue disk or otherwise have anaconda
locally there are a couple of issues.  When you tell it where the
install tree is (ie: a remote FTP site) the first time it tries to
download anything is for getting package headers.  If the path you
entered is wrong the user doesn't know until almost the end of the
install.  The error dialog you get says "Unable to read header list. 
This may be due to a missing file or bad media.  Press <return>..." 
VT3 has 5 errors about fetching the hdlist.

It should test the valitity of the server/path as soon as possible.

Also, this method doesn't find or use the remote product.img.  (Not
like a really care but...)