Yes you can, if you want heroes and items from maps A and B loadable into map C.
You will need to recreated EVERY hero and item you want to have in map C. Once you've done that you need the raw codes to make them saveable.
Say for example that this is your save trigger that saves ONLY specific heroes:
Code:
function Trig_Class_Array_Setup_Actions takes nothing returns nothing
set udg_Class_List_Array_BitsRq = 5
// ------------------------
set udg_Temp_Integer = 0
set udg_Class_List_Array[udg_Temp_Integer] = 'Hpal'
// ------------------------
set udg_Temp_Integer = ( udg_Temp_Integer + 1 )
set udg_Class_List_Array[udg_Temp_Integer] = 'Hamg'
// ------------------------
set udg_Temp_Integer = ( udg_Temp_Integer + 1 )
set udg_Class_List_Array[udg_Temp_Integer] = 'E003'
Lets call the 'Hpal, 'Hamg' and 'E003' = Your hero raw codes. If you want to do a item save this is the exact same except with different wordings
Code:
function Trig_Item_Array_Setup_Actions takes nothing returns nothing
set udg_Item_List_Array_BitsRq = 6
// ------------------------
set udg_Temp_Integer = 0
// First Item in list Must be NO ITEM!!!!
set udg_Item_List_Array[udg_Temp_Integer] = GetItemTypeId(null)
// ------------------------
set udg_Temp_Integer = ( udg_Temp_Integer + 1 )
set udg_Item_List_Array[udg_Temp_Integer] = 'I00P'
All you need to do is copy and paste this part:
Code:
// ------------------------
set udg_Temp_Integer = ( udg_Temp_Integer + 1 )
set udg_Item_List_Array[udg_Temp_Integer] = 'I00P'
Remove the "I00P" and put in your raw item code. Same with the hero save trigger listed above. Hoped this helped.

Edit : This save system is pretty simple, if its different from yours, all you need to do is find the 4 digit raw code, copy and paste it in the pattern your save system (like show above) and change it do your specific hero / item.