CK tip, quickly finding our modded content

[sandor]

Go to the cell view window. For example you're looking for a interior cell. Make sure you loaded the interiors.
Move the mouse pointer to the border of the FormID and Name and enlarge the FormID area.
Click twice on the FormID list to change the sort order, our interiors are on top (Mod Index 02).

The same applies to our other content (everything that starts with 02)

FYI
Form ID's Mod Index.
[tm=yellow]00[/tm]xxxxxx = Skyrim.esm
[tm=yellow]01[/tm]xxxxxx = Update.esm
[tm=yellow]02[/tm]xxxxxx = Silgrad_Tower.esm