FileWave Inventory
The current release of FileWave Inventory will not work on a default install of OS X Snow Leopard.  This reason for this is that the Inventory component uses the default OS X PHP library.  Snow Leopard ships with PHP version 5.3.  IonCube in turn has not released a loader for this paticular PHP version.

A workaround would be to downgrade the PHP library to 5.2.6 but it's recomended to simply wait until a new release of Inventory is published which will use a MAMP style server install.

As of FileWave 3.7.2, there are a few known issues with FileWave running in OS X Snow Leopard, all of which stem from how Snow Leopard handles the setuid bit on executables owned by root.

Client
FileWave FWGui.app presents a dialog upon login and requires to authenticate as an admin.
The fwGUI process will not start because it uses the setuid bit. As a result the notification window doesn't appear on the client machine when installers are delivered which require a reboot. Reboot installers are only executed when the user account is logged off.