[This is preliminary documentation and subject to change.]
In order to run your loader, you must make sure the Loadstub component (Loadstub.exe) is informed about it. You do this by adding an entry to the registry and causing Task Scheduler to pass this entry to Loadstub when Loadstub calls your loader.
Loadstub.exe searches for your loader's entry in the following registry key:
HKEY_LOCAL_MACHINE\Software\Microsoft\TV Services\Guide\Loaders.
The name of the entry should be the globally unique identifier (GUID) for the loader, enclosed within curly braces ({}). If you have installed Microsoft® WebTV® for Windows®, you can use the entry for the default loader as an example of such an entry. You must add a name string value to the new entry that gives the complete path to your loader. You can also include any parameters your loader requires in this entry; for more information on what is required in your loader's registry entry, see Loaders Subkey. When Loadstub is run, Loadstub adds values to the registry entry for your loader's last attempted run time, last completed run time, and last completed result.
Once the registry contains the new entry, you can run your loader with the following command line:
loadstub /L:{00000000-0000-0000-0000-000000000000}
where the number between the curly braces is the GUID for your loader.
When you have verified that your loader is working properly, you can set it to run at regular intervals. You do so by adding the preceding command line to the scheduled tasks list in Task Scheduler.