This works well at least when built on linux.
Great stuff
I guess it would be helpful to also take the textures from the original file and put them together with the .ter file into a new .eqg file so the same renderer code will work on new and old zones.
Also, you might want to make sure you open the files with "rb" and "wb" instead of "w" and "b" for portability. (Not that it works properly on windows at this time even with that changce for some reason)