are you saving it as a .fpe ?
this works fine for me saved as humvee.fpe
;header
desc = Humvee
;ai
aiinit = appear1.fpi
aimain = default.fpi
aidestroy = disappear1.fpi
;spawn
spawnmax = 0
spawndelay = 0
spawnqty = 0
;orientation
model = meshbank\modernday\scenery\special\humvee\humvee.x
offx = 0
offy = 0
offz = 0
rotx = 0
roty = 0
rotz = 0
defaultstatic = 1
materialindex = 3
;visualinfo
textured = texturebank\modernday\scenery\special\humvee\humvee_D2.dds
effect = effectbank\bumpent\bumpent.fx
castshadow = 0
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