void main()
{
    int nActive = GetLocalInt(OBJECT_SELF, "tri_crsActive");
    object oPC = GetLastUsedBy();

    if(!nActive == 0)
    {
    ActionStartConversation(oPC);
    }

    else
    {
    SendMessageToPC(oPC, "You touch the crystal ball, but nothing seems to happen");
    }

}