Is it possible to create additional Collada meshes of LEGO NXT parts?

edit

I have built a robotic arm in Lego Digital Designer (as well as the physical world), and run the resulting .lxf and .ldr files through the nxt_lxf2urdf package. I then roslaunch the robot and up come the motor/sensor topics. So far, so good. When I try to visualize the robot in RViz, it spits out a bunch of errors:

[ERROR] [1314217186.037324443]: Could not load resource [package://nxt_description/meshes/parts/3737.dae]: Unable to open file "package://nxt_description/meshes/parts/3737.dae".
[ERROR] [1314217186.063642125]: Could not load model 'package://nxt_description/meshes/parts/3737.dae' for link 'ref_103_link': OGRE EXCEPTION(6:FileNotFoundException): Cannot locate resource package://nxt_description/meshes/parts/3737.dae in resource group Autodetect or any other group. in ResourceGroupManager::openResource at /tmp/buildd/ros-diamondback-visualization-common-1.4.1/debian/ros-diamondback-visualization-common/opt/ros/diamondback/stacks/visualization_common/ogre/build/ogre_src_v1-7-1/OgreMain/src/OgreResourceGroupManager.cpp (line 753)

[ERROR] [1314217186.081540366]: Could not load resource [package://nxt_description/meshes/parts/3649.dae]: Unable to open file "package://nxt_description/meshes/parts/3649.dae".

and so on for about 10 Collada meshes. Looking at the nxt_lxf2urdf wiki page, it states:

Currently nxt_dscriptions has a subset of the ldraw.org parts library converted to Collada meshes, so not all parts will be modelled in rviz. We are still looking for ways to make converting the ldraw models to Collada.

Thanks!

Ian