You can access the shares using a fix that's been around for awhile for this issue...a logon script.
You need to create a directory on your MC box and share it out as netlogon. In there, put a logon script that maps a drive to the music, photo, etc directories on the server, using an account that has access to those shares (net use * \\server\music /u:server\username password)
Then in computer management on the media center, open the properties of the MCX user account and type the name of your logon script in the profile (eg: logon.bat).
Also keep in mind that HS is a v1 product.