To create a new hoteldruid theme make a copy of the "sim"
directory inside the "themes" directory of hoteldruid and
rename it with a new name of 3 letters. Then edit the theme
names in the "name.php" file inside the "php" subdirectory of
the new theme. Now you will be able to select the new theme
from "configure and customize".

In the "php" subdirectory you have the files that are actually
used by hoteldruid. You can modify the head and foot of all
hoteldruid pages from "head.php" and "foot.php" files. In
file "menu.php" you can set the variable $hide_default_menu to
true and insert there a new main menu page. Lastly the dates
lists are generated from the file "selectperiod.php".

The other subdirectories are optional and you can delete or
modify them as needed by your theme.