Once again the files for areas are not called maps. Or tilesets for that matter. Each area made up of multiple usually an average of 10 seperate model files. These area model files are then layed out using a layout file.(.lyt)
As for Fillers and blocks they would have really not much meaning or use to me.
As too modify the area models mesh like you would a head model the theory is correct. However the model itself is so large in scale that our current model compiler/decompiler tool(mdlops) can't properly handle using the Mesh replacer function in the replacer tool. This is because the size of the area model is outside of the scope of mdlops.
I've been working on a new model tool based off mdlops so as to be able to try to manage the larger area models but I'm probably a week or 2 off from an alpha release.
If your familiar with the CAD scripting language and manage to create a CAD script to import models with I'll gladly provide a export to CAD file option or whatever format AutoCAD uses. That's one of the things I'm doing for the model tool now is building a direct export to 3ds & gmax format by going through NWMax's script files.
Working so, we will learn history as a tree knows it; we will climb into shapes printed in the seed; we will become time made visible, years made fragrant; we will make of concentric memory a stem of praise; we will inhabit daylight at a trees own speed; we will be travelers who remain, patriots to this ground.
OMG I only rank 62.13018% geek or a Extreme Geek as it is referred to on the geektest at Geektest