Open the entitybank folder and pick a model like a crate or something simple. There are 3 files to be concerned in adding entities.
1) modelname.fpe
2) modelname.bmp
3) modelname.x
The modelname.bin and modelname.dbo are generated by FPSC when placed in the map editior, so don't worry about those for now.
Take the modelname.fpe and study it. You should be able to use the information for learning how to do this. If nothing else, use it as a template for your import. Remember, the model in the map editor is recognized as being in existence because of the fpe file.
~Dave
Phoenix Sentry Programmer