I have added a new feature to ModelConverterX yesterday, the ability to show the normals of your object. The prime reason to do this now was that it gave me a good debugging feature to see if the SCASM code was read in correctly. But also for end users this can be useful, as it shows you if the normals of your model have been defined correctly. This has an influence on how your model is lighted in the scenery.
Another nice feature I have added is that you can save the preview image to your disk. So that allows you to use it as a thumbnail in your placement program for example. At the moment you have to save the image manually, but I plan to make it an automatic option as well (and include it in the batch convert functions).