extract the files with e.g. winrar to your Fallout3/Data Folder and activate them trough FOMM

what the files do:
- update the NPC's pathfinding (no more going into ssandbags etc.)

appreciated load order:

if you use both mods:

(all other mods)
- outcast stronger FI
- str FI compatible file for FI improved
- no ramp file (necessary for the navmesh file to work properly!)
- FI improved both main files
- FI impr compatible file for stro FI
- the both-mods-navmesh file

if you use only stronger FI:

(all other mods)
- outcast stronger FI
- no ramp file (if you use it)
- the StrongerFI-only-navmesh file
- the ramp navmesh file (ONLY if you have the ramp)

recommed tools:
fallout mod manager
winRar

credits to:
- bethesda for F3 and the G.E.C.K.
- bikkebakke
- me :)