This map has always been broken. This variant makes it slightly less broken (although something changed on the ceiling might prevent hiding on pixels on the slope). What will finally fix it is either moving nets closer together or adding angle bounce to hedgehogs or some other layout that prevents hiding.
/*
** $Id: lualib.h,v 1.36.1.1 2007/12/27 13:02:25 roberto Exp $
** Lua standard libraries
** See Copyright Notice in lua.h
*/
#ifndef lualib_h
#define lualib_h
#include "lua.h"
/* Key to file-handle type */
#define LUA_FILEHANDLE "FILE*"
#define LUA_COLIBNAME "coroutine"
LUALIB_API int (luaopen_base) (lua_State *L);
#define LUA_TABLIBNAME "table"
LUALIB_API int (luaopen_table) (lua_State *L);
#define LUA_IOLIBNAME "io"
LUALIB_API int (luaopen_io) (lua_State *L);
#define LUA_OSLIBNAME "os"
LUALIB_API int (luaopen_os) (lua_State *L);
#define LUA_STRLIBNAME "string"
LUALIB_API int (luaopen_string) (lua_State *L);
#define LUA_MATHLIBNAME "math"
LUALIB_API int (luaopen_math) (lua_State *L);
#define LUA_DBLIBNAME "debug"
LUALIB_API int (luaopen_debug) (lua_State *L);
#define LUA_LOADLIBNAME "package"
LUALIB_API int (luaopen_package) (lua_State *L);
/* open all previous libraries */
LUALIB_API void (luaL_openlibs) (lua_State *L);
#ifndef lua_assert
#define lua_assert(x) ((void)0)
#endif
#endif