Game Crashing?

library OER initializer init uses Callbacks
    globals
        private trigger OnEnter
        private Table cbs
    endglobals
   
    private function interface Oni takes nothing returns nothing
    
    private function H2I takes handle h returns integer
        return h
        return 0
    endfunction
    
   struct OERS
        rect rct
        region r
        Oni callback
        boolean enter
    endstruct
   
    private function OnEnterFunc takes nothing returns nothing
        local region r = GetTriggeringRegion()
        local unit u = GetEnteringUnit()
        local OERS oz = cbs[H2I(r)]
        local Oni i = oz.callback
        
        set CALLBACK_RESPONDER = u
        set CALLBACK_STRUCT = oz
        call i.execute()
    endfunction
    
    function RegisterEnterRect takes rect rct, boolean enter, boolexpr cond, Oni i returns nothing
        local region r = CreateRegion()
        local OERS oz = OERS.create()
        local integer I
        call RegionAddRect(r, rct)
        
        set oz.rct = rct
        set oz.r = r
        set oz.callback = i
        set oz.enter = enter
        set I = H2I(r)
        set cbs[i] = oz
        set cbs[H2I(rct)+I] = oz
        if(enter)then
            call TriggerRegisterEnterRegion(OnEnter, r, cond)
        else
            call TriggerRegisterLeaveRegion(OnEnter, r, cond)
        endif
    endfunction
    
    function DeleteEnterRect takes OERS s, boolean removerect returns nothing
        if(s == 0)then
            return
        endif

        set cbs[H2I(s.r)] = 0
        set cbs[H2I(s.r) + H2I(s.rct)] = 0

        if(removerect)then
            call RemoveRect(s.rct)
            set s.rct = null
        endif
        call RemoveRegion(s.r)
        set s.r = null
        call s.destroy()
    endfunction
    
    private function init takes nothing returns nothing
        set OnEnter = CreateTrigger()
        call TriggerAddAction(OnEnter, function OnEnterFunc)
        set cbs = Table.create()
    endfunction
endlibrary