You say you see nothing. But did you add a camera to your scene and is it located at a spot where you can see stuff?
Greetings,
the export code of the model is below
<?xml version='1.0' encoding='UTF-8'?>
<world>
<plugins>
<plugin name='genmesh'>crystalspace.mesh.loader.genmesh</plugin>
<plugin name='genmeshfact'>crystalspace.mesh.loader.factory.genmesh</plugin>
</plugins>
<shaders/>
<textures>
<texture name='oldbrickDOT3.png'>
<file>/lib/stdtex/oldbrickDOT3.png</file>
</texture>
<texture name='colors.jpg'>
<file>/lib/stdtex/colors.jpg</file>
</texture>
</textures>
<materials/>
<sounds/>
<settings>
<clearscreen>yes</clearscreen>
<clearzbuf>yes</clearzbuf>
</settings>
<library>factories/genCube.001</library>
<library>factories/genCube.004</library>
<library>factories/genCube.008</library>
<triggers/>
<sector name='Scene'>
<portals name='Mesh'>
<portal>
<v y='-2.52000021935' x='-9.95999908447' z='2.4799990654'/>
<v y='-5.04000043869' x='-9.95999908447' z='2.47999978065'/>
<v y='-5.04000043869' x='-9.95999908447' z='5.0'/>
<v y='-2.52000021935' x='-9.95999908447' z='4.99999952316'/>
<sector>Scene.001</sector>
</portal>
<priority>portal</priority>
<hardmove>
<v y='0' x='0' z='0'/>
<matrix/>
</hardmove>
</portals>
<cullerp plugin='crystalspace.culling.frustvis'/>
<light name='Lamp.003'>
<center y='-2.42516' x='-13.4606' z='2.0713'/>
<color blue='1.0' green='1.0' red='1.0'/>
<radius brightness='1.0'>29.9999828339</radius>
</light>
<meshobj name='Cube'>
<plugin>genmesh</plugin>
<params>
<factory>genCube.001</factory>
<material>colors.jpg</material>
</params>
<zuse/>
<move>
<v y='0' x='0' z='0'/>
</move>
</meshobj>
<light name='Lamp'>
<center y='2.23661' x='-13.4606' z='6.79522'/>
<color blue='1.0' green='1.0' red='1.0'/>
<radius brightness='1.0'>29.9999828339</radius>
</light>
</sector>
<sector name='Scene.001'>
<portals name='Cube.001'>
<portal>
<v y='-5.04000043869' x='-9.95999908447' z='2.47999978065'/>
<v y='-2.52000021935' x='-9.95999908447' z='2.4799990654'/>
<v y='-2.52000021935' x='-9.95999908447' z='4.99999952316'/>
<v y='-5.04000043869' x='-9.95999908447' z='5.0'/>
<sector>Scene</sector>
<clipstraddling/>
</portal>
<priority>portal</priority>
<hardmove>
<v y='0' x='0' z='0'/>
<matrix/>
</hardmove>
</portals>
<portals name='Cube.002'>
<portal>
<v y='-5.04000043869' x='-4.95999908447' z='2.47999978065'/>
<v y='-5.04000043869' x='-4.95999908447' z='5.0'/>
<v y='-2.52000021935' x='-4.95999908447' z='4.99999952316'/>
<v y='-2.52000021935' x='-4.95999908447' z='2.4799990654'/>
<sector>Scene.002</sector>
<clipstraddling/>
</portal>
<priority>portal</priority>
<hardmove>
<v y='0' x='0' z='0'/>
<matrix/>
</hardmove>
</portals>
<cullerp plugin='crystalspace.culling.frustvis'/>
<meshobj name='Cube.003'>
<plugin>genmesh</plugin>
<params>
<factory>genCube.004</factory>
<material>oldbrickDOT3.png</material>
</params>
<zuse/>
<move>
<v y='0' x='0' z='0'/>
</move>
</meshobj>
<light name='Lamp.001'>
<center y='-4.16555' x='-6.86073' z='3.61185'/>
<color blue='1.0' green='1.0' red='1.0'/>
<radius brightness='1.0'>29.9999828339</radius>
</light>
</sector>
<sector name='Scene.002'>
<portals name='Mesh.001'>
<portal>
<v y='-5.04000043869' x='-4.95999908447' z='5.0'/>
<v y='-5.04000043869' x='-4.95999908447' z='2.47999978065'/>
<v y='-2.52000021935' x='-4.95999908447' z='2.4799990654'/>
<v y='-2.52000021935' x='-4.95999908447' z='4.99999952316'/>
<sector>Scene.001</sector>
</portal>
<priority>portal</priority>
<hardmove>
<v y='0' x='0' z='0'/>
<matrix/>
</hardmove>
</portals>
<cullerp plugin='crystalspace.culling.frustvis'/>
<light name='Lamp.004'>
<center y='1.55288' x='-2.99508' z='2.45526'/>
<color blue='1.0' green='1.0' red='1.0'/>
<radius brightness='1.0'>29.9999828339</radius>
</light>
<meshobj name='Cube.007'>
<plugin>genmesh</plugin>
<params>
<factory>genCube.008</factory>
<material>colors.jpg</material>
</params>
<zuse/>
<move>
<v y='0' x='15' z='0'/>
</move>
</meshobj>
<light name='Lamp.002'>
<center y='1.55288' x='2.00199' z='6.22663'/>
<color blue='1.0' green='1.0' red='1.0'/>
<radius brightness='1.0'>29.9999828339</radius>
</light>
</sector>
<sequences/>
<start name='Camera'>
<sector>Scene</sector>
<position y='5.34367' x='7.48113' z='-6.50764'/>
<up y='0.895343' x='-0.330657' z='0.298373'/>
<forward y='-0.445245' x='-0.654862' z='0.610666'/>
</start>
<start name='Camera.001'>
<sector>Scene.001</sector>
<position y='5.34367' x='7.48113' z='-6.50764'/>
<up y='0.895343' x='-0.330657' z='0.298373'/>
<forward y='-0.445245' x='-0.654862' z='0.610666'/>
</start>
<start name='Camera.002'>
<sector>Scene.002</sector>
<position y='5.34367' x='7.48113' z='-6.50764'/>
<up y='0.895343' x='-0.330657' z='0.298373'/>
<forward y='-0.445245' x='-0.654862' z='0.610666'/>
</start>
</world>