Script might well override a static map, but can't risk it not doing it, and preview completely failing. Better to just not try it for static maps. Some script cfg might help. Could also avoid unnnecessary preview regenerations even if the script was doing nothing at all.
/*
** $Id: ltable.h,v 2.10.1.1 2007/12/27 13:02:25 roberto Exp $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/
#ifndef ltable_h
#define ltable_h
#include "lobject.h"
#define gnode(t,i) (&(t)->node[i])
#define gkey(n) (&(n)->i_key.nk)
#define gval(n) (&(n)->i_val)
#define gnext(n) ((n)->i_key.nk.next)
#define key2tval(n) (&(n)->i_key.tvk)
LUAI_FUNC const TValue *luaH_getnum (Table *t, int key);
LUAI_FUNC TValue *luaH_setnum (lua_State *L, Table *t, int key);
LUAI_FUNC const TValue *luaH_getstr (Table *t, TString *key);
LUAI_FUNC TValue *luaH_setstr (lua_State *L, Table *t, TString *key);
LUAI_FUNC const TValue *luaH_get (Table *t, const TValue *key);
LUAI_FUNC TValue *luaH_set (lua_State *L, Table *t, const TValue *key);
LUAI_FUNC Table *luaH_new (lua_State *L, int narray, int lnhash);
LUAI_FUNC void luaH_resizearray (lua_State *L, Table *t, int nasize);
LUAI_FUNC void luaH_free (lua_State *L, Table *t);
LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
LUAI_FUNC int luaH_getn (Table *t);
#if defined(LUA_DEBUG)
LUAI_FUNC Node *luaH_mainposition (const Table *t, const TValue *key);
LUAI_FUNC int luaH_isdummy (Node *n);
#endif
#endif