That should have worked.  Try this: 
 
#spawn Test 
 
/target Test 
 
#npcspawn create 
 
See if that NPC remains or not (it should).  If so, the add command should work fine on your other NPC, assuming the #dbspawn <id> command worked to spawn it after you created it. 
		
	
		
		
		
		
		
		
			
		
		
		
		
		
		
	
		
		
	
	
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