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: lapi.h,v 2.2.1.1 2007/12/27 13:02:25 roberto Exp $
** Auxiliary functions from Lua API
** See Copyright Notice in lua.h
*/
#ifndef lapi_h
#define lapi_h
#include "lobject.h"
LUAI_FUNC void luaA_pushobject (lua_State *L, const TValue *o);
#endif