This should deal with issue 461.

QuestHelper/collect_merchant.lua

@@ -45,11 +45,12 @@ local function MerchantShow()
     dstr.avail = avail
     dstr.price = price
     --if debug_output then QuestHelper:TextOut(dstr) end
-    if not targ["shop"][itemid] then 
-      targ["shop"][itemid] = dstr
+    if not targ.shop then targ.shop = {} end
+    if not targ.shop[itemid] then 
+      targ.shop[itemid] = dstr
     end
 
-    targ["shop"][itemid].count = (targ["shop"][itemid].count or 0) + 1
+    targ.shop[itemid].count = (targ.shop[itemid].count or 0) + 1
   end
 end