Preferences
Allows you to set preferences for various aspects of the editor, mainly having to do with how the Render Window looks and operates.
Grid Snap / Use Grid
When Use Grid is checked, objects shown in the Render Window move only by the number of units in the "Grid Snap" field. This can be helpful when lining up room pieces. Multiples of 8 are effective with the original objects (32, 64, 128).
Angle Snap / Use Angle
When "Use Angle" is checked, objects in the Render Window will rotate as many degrees as are specified in the "Angle Snap" field. Again, this is helpful when attempting to line up many objects.
Cell Load Settings
"Allow Render Window Cell Loads" will load the full cell every time the user selects an object in a cell adjacent to the exterior cell currently being worked on. "Skip Initial Cell Load" will prevent the editor from loading the first cell in the list into the Render Window when an esm/ess file is loaded.
Movement Speeds
Numbers can be entered to change the speed at which the user rotates and moves both the camera and objects. The default values are 1.00.
View Settings
The slider bar in this section controls how much of the loaded cell will be visible in the Render Window. The farther towards "far" the slider is set, the more can be seen from any given camera position, which may slow down some systems. The "Renderer Settings" button brings up options for display device used by the Editor.
Auto Save
When checked, this option automatically backs up the user's work on a regular basis, as specified by the number of minutes entered. This backup file is called AutoSave.bak and is a regular plugin. Just rename it to restore your work.