They created different code depending on the passed index, this was changed to always emit the optional parameter, even when not needed, so that the interpreter does not need to second-guess.
Not everything will do something, though. This was some incredibly careless code operating without a safety net allowing uncontrolled write access to the map structure.
Most of the critical fields have been made read-only, which has been the only mode of access in the mods I checked.
Note that this does not enable scripting of the weapon sprite drawer, only the gameplay related features were done.
