I have completed Kaos' Fortress story level several times (nightmare mode), and even though I have checked in the known locations for all 5 treasure chests (based on reading other walkthroughs), the level still shows that I have found only 4 out of 5 treasure chests. Yet, in each area where a treasure chest is supposed to be, I find only a diamond to collect. Anyone have any advice? It will so frustrate me to have this star un-earned, when there's nothing I can do to make the treasure chest re-appear, even though I've collected it already!!
I have completed the level - it never shows under Objectives that I have collected all 5 treasure chests, even though there are no more chests in the locations. Good suggestion, because that happened to me with another level, but on that one the objectives correctly listed as completed, just the star wouldn't show until I did the entire level completed. In this case, I have completed the level to the end several times...
Thanks for trying - any other ideas?