diff --git a/src/GlobalState.lua b/src/GlobalState.lua
index c803921..7ad6b62 100644
--- a/src/GlobalState.lua
+++ b/src/GlobalState.lua
@@ -76,7 +76,6 @@ function M.inner_setup()
   end
 
   if global.mod.scan_queues == nil or true then
-    global.mod.entity_priority = {} -- key=unum, val=priority
     M.reset_queues()
   end
 
@@ -168,7 +167,8 @@ function M.reset_queues()
 
   global.mod.scan_queues = {} -- list of queues to process
   for idx = 1, constants.QUEUE_COUNT do
-    global.mod.scan_queues[idx] = Queue.new()
+    -- key=unit_nubmer, val=priority
+    global.mod.scan_queues[idx] = {}
   end
 
   if global.mod.chests ~= nil then
@@ -904,15 +904,13 @@ end
   That will put the entity in the previous queue slot.
 ]]
 function M.queue_insert(unit_number, priority)
-  -- clamp priority to 0 .. QUEUE_COUNT-2
+  -- clamp priority to 0..QUEUE_COUNT-2 (inclusive)
   priority = math.max(0, math.min(priority, constants.QUEUE_COUNT - 2))
-  -- save the priority for next time
-  global.mod.entity_priority[unit_number] = priority
 
   -- q_idx is where to put it, Priority 0 => scan_index + 1
   -- scan_index is 1-based, so we subtract 1 and then add 1 (scan_index - 1 + 1 + priority)
   local q_idx = 1 + (global.mod.scan_index + priority) % constants.QUEUE_COUNT
-  Queue.push(global.mod.scan_queues[q_idx], unit_number)
+  global.mod.scan_queues[q_idx][unit_number] = priority
 
   --print(string.format("[%s] ADD  q %s unum %s si=%s p=%s qx=%s", game.tick, q_idx, unit_number, global.mod.scan_index, priority, constants.QUEUE_COUNT))
 end
@@ -930,14 +928,14 @@ function M.update_queue_lists(update_entity)
     .value
 
   local qs = global.mod.scan_queues
-  local q_idx = global.mod.scan_index
+  local q_idx = global.mod.scan_index or 1
   if q_idx < 1 or q_idx > #qs then
     q_idx = 1
   end
   local q = qs[q_idx]
 
   for _ = 1, MAX_ENTITIES_TO_UPDATE do
-    local unit_number = Queue.pop(q)
+    local unit_number, old_pri = next(q)
     if unit_number == nil then
       -- nothing to process in this queue. step to the next one if past the deadline
       if game.tick >= (global.mod.scan_deadline or 0) then
@@ -947,10 +945,10 @@ function M.update_queue_lists(update_entity)
       end
       return
     end
-    --print(string.format("[%s] PROC q %s unum %s", game.tick, q_idx, unit_number))
+    q[unit_number] = nil
+    --print(string.format("[%s] PROC q %s unum=%s pri=%s", game.tick, q_idx, unit_number, old_pri))
 
     -- the UPDATE_STATUS are actually relative priorities.
-    local old_pri = global.mod.entity_priority[unit_number] or 0
     local pri_adj = update_entity(unit_number, old_pri)
     -- nil means entity is invalid.
     if pri_adj ~= nil then
diff --git a/src/NetworkChest.lua b/src/NetworkChest.lua
index bc75132..c9e9cbb 100644
--- a/src/NetworkChest.lua
+++ b/src/NetworkChest.lua
@@ -730,7 +730,7 @@ local function update_network_chest_configured_common(info, inv, contents)
       local n_free = GlobalState.get_insert_count(item)
       local n_transfer = math.min(n_extra, n_free)
       if n_transfer > 0 then
-        status = GlobalState.UPDATE_STATUS.UPDATED
+        -- status = GlobalState.UPDATE_STATUS.UPDATE_PRI_INC
         inv.remove({name=item, count=n_transfer})
         GlobalState.increment_item_count(item, n_transfer)
         info.recent_items[item] = game.tick
@@ -1056,7 +1056,10 @@ local function update_entity_chest(unit_number, info)
   elseif entity.name == "network-chest-requester" then
     update_network_chest_requester(info)
     return GlobalState.UPDATE_STATUS.UPDATE_BULK
+  else
+    clog("What is this chest? %s", entity.name)
   end
+  return GlobalState.UPDATE_STATUS.NOT_UPDATED
 end
 
 local function update_entity_tank(unit_number, info)
@@ -1086,27 +1089,43 @@ local function update_entity(unit_number, priority)
   info = GlobalState.get_chest_info(unit_number)
   if info ~= nil then
     info.service_tick = game.tick
-    return update_entity_chest(unit_number, info, priority)
+    local retval = update_entity_chest(unit_number, info)
+    if retval == nil then
+      clog("chest drop: %s", serpent.line(info))
+    end
+    return retval
   end
 
   info = GlobalState.get_tank_info(unit_number)
   if info ~= nil then
     info.service_tick = game.tick
-    return update_entity_tank(unit_number, info, priority)
+    local retval = update_entity_tank(unit_number, info)
+    if retval == nil then
+      clog("tank drop: %s", serpent.line(info))
+    end
+    return retval
   end
 
   local entity = GlobalState.get_logistic_entity(unit_number)
   if entity ~= nil then
-    return M.update_entity_logistic(entity)
+    local retval = M.update_entity_logistic(entity)
+    if retval == nil then
+      clog("logistic drop: %s", serpent.line(info))
+    end
+    return retval
   end
 
   entity = GlobalState.get_vehicle_entity(unit_number)
   if entity ~= nil then
-    return M.update_entity_vehicle(entity)
+    local retval = M.update_entity_vehicle(entity)
+    if retval == nil then
+      clog("vehicle drop: %s", serpent.line(info))
+    end
+    return retval
   end
 
   -- unknown/invalid unit_number
-  clog("Dropped: unum %s", unit_number)
+  clog("Dropped: unknown unum %s", unit_number)
   return nil
 end