Modified X-treme Theme - Would like to hide themes from other Multi Gallery Users

I have a multigallery installation and have different X_treme themes set up for each user with their logos, info, etc. I would like to hide the "User 1" theme to prevent "User 2" from installing "User 1"'s theme and vice versa.

Any ideas on how to accomplish this?

Gallery version = 2.2.2 core 1.2.0.4
PHP version = 4.3.11 cgi-fcgi
Webserver = Apache
Database = mysqlt 5.0.37-log, lock.system=database
Toolkits = LinkItemToolkit, Thumbnail, Gd, ImageMagick, SquareThumb
Acceleration = none, none
Operating system = Linux p3slh024.shr.phx3.secureserver.net 2.4.21-47.0.1.ELsmp #1 SMP Fri Oct 13 17:56:20 EDT 2006 i686
Default theme = x_treme_Kate
gettext = enabled
Locale = en_US
Browser = Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4
Rows in GalleryAccessMap table = 18
Rows in GalleryAccessSubscriberMap table = 6
Rows in GalleryUser table = 2
Rows in GalleryItem table = 4
Rows in GalleryAlbumItem table = 3
Rows in GalleryCacheMap table = 0

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