My bad. After a quick look at the script, the culprit is "compositefl 80.gsm", a binary macro from a 3ds file.
Curiously, this macro is still present in 15 INT library, despite it is not used by any object, IMHO. Search for the error.
Replacing this macro by few lines of GDL code, polycount can be reduced at 15 000 aprox.
The best I can do. I think it can do the trick.