Uncategorized even when another category is selected

Normally you can just select which categories users should be allowed to select from the dropdown menu (the setting for this is called “Categories”. To require a specific category, say, without displaying the category field, you can create a custom form as explained in the readme.txt. Then inside the custom form template add a hidden field like so:

<input name="user-submitted-category" value="3" type="hidden" />

..and change “3” to the ID of whichever category you would like to require.