There are 2 types of docklet for OD.
One type is 'hard-coded' i.e it's in the form of a DLL and only has a single purpose/function. It's configurability is limited to what the porgrammer provides when the docklet is designed.
The other type is like SysStats which is a generic environment to support all sorts of functions that can be displayed as a docklet in OD. SysStats is configured with it's own GUI and saves it in an .ini file but will also support images and scripting etc and can access to the Windows WMI (hardware monitoring) API.
So the answer to your question depends on which type you're using...
Typically, unless you want custom docklets it's easier to use a pre-existing one from the OD galleries at Wincustomize, DockEx or the SysStats homepage.
