diff --git a/AndorsTrail/src/com/gpl/rpg/AndorsTrail/controller/MapController.java b/AndorsTrail/src/com/gpl/rpg/AndorsTrail/controller/MapController.java
index 2dcf06894..acced11b8 100644
--- a/AndorsTrail/src/com/gpl/rpg/AndorsTrail/controller/MapController.java
+++ b/AndorsTrail/src/com/gpl/rpg/AndorsTrail/controller/MapController.java
@@ -186,6 +186,13 @@ public final class MapController {
 				if (!satisfiesCondition(replacement)) continue;
 				else ConversationController.requirementFulfilled(world, replacement.requirement);
 				tileMap.applyReplacement(replacement);
+				for (ReplaceableMapSection impactedReplacement : tileMap.replacements) {
+					if (impactedReplacement.isApplied && impactedReplacement.replacementArea.intersects(replacement.replacementArea)) {
+						//The applied replacement has overwritten changes made by a previously applied replacement.
+						//This previous replacement must now be considered as unapplied to let it be reapplied later eventually.
+						impactedReplacement.isApplied = false;
+					}
+				}
 				hasUpdated = true;
 			}
 		}
diff --git a/AndorsTrail/src/com/gpl/rpg/AndorsTrail/model/map/TMXMapTranslator.java b/AndorsTrail/src/com/gpl/rpg/AndorsTrail/model/map/TMXMapTranslator.java
index c85491380..aed27b394 100644
--- a/AndorsTrail/src/com/gpl/rpg/AndorsTrail/model/map/TMXMapTranslator.java
+++ b/AndorsTrail/src/com/gpl/rpg/AndorsTrail/model/map/TMXMapTranslator.java
@@ -288,7 +288,8 @@ public final class TMXMapTranslator {
 						else if (prop.name.equalsIgnoreCase(LAYERNAME_ABOVE)) layerNames.aboveLayersName = prop.value;
 						else if (prop.name.equalsIgnoreCase(LAYERNAME_WALKABLE)) layerNames.walkableLayersName = prop.value;
 						else if (AndorsTrailApplication.DEVELOPMENT_VALIDATEDATA) {
-							L.log("OPTIMIZE: Map " + map.name + " contains replace area with unknown property \"" + prop.name + "\".");
+							if (!requirementPropertiesNames.contains(prop.name))
+								L.log("OPTIMIZE: Map " + map.name + " contains replace area with unknown property \"" + prop.name + "\".");
 						}
 					}
 					MapSection replacementSection = transformMapSection(map, tileCache, position, layersPerLayerName, usedTileIDs, layerNames);