[Vpmedia]

for starters you need the sfs extractor, .net 2,0 & imf viewer to extract and convert images into readable format

3 important releases which you may want to study:
Flushmeisters bumpification mod, Default map upgrade pack http://files.filefront.com/vp+default+m ... einfo.html, Texture library for mapbuilders: http://files.filefront.com/vp+il2textur ... einfo.html available at my site

I would start by extracting all map related files and understanding the file structure

cheers