Scripts

I don't know – I can only guess;

I tried recording this value: MarkObjectAsVisited(sObjectID, true);
where sObjectID is the script name of the object.

There's something wrong with the loops; try disabling the object in a different way, for example, by naming all three stones differently: stone01, stone02, stone03, and then selecting them in the script:

stone = {'stone01', 'stone02', 'stone03'};
stone.n = length(stone);
...
for i=1, stone.n do
    SetObjectEnabled (stone,nil);
    Trigger (OBJECT_TOUCH_TRIGGER,stone,'up_herolider'); 
end;
...