diff --git a/NHSE.Core/Structures/Villager/PlayerHouse2.cs b/NHSE.Core/Structures/Villager/PlayerHouse2.cs
index 17df7e6..093bccb 100644
--- a/NHSE.Core/Structures/Villager/PlayerHouse2.cs
+++ b/NHSE.Core/Structures/Villager/PlayerHouse2.cs
@@ -58,7 +58,7 @@ public PlayerHouse1 Downgrade()
             var data = new byte[PlayerHouse1.SIZE];
             Data.Slice(0x0, 0x120).CopyTo(data, 0); // HouseLevel -> EventFlag
             for (int i = 0; i < MaxRoom; i++)
-                ((PlayerRoom2)GetRoom(i)).Downgrade().Data.CopyTo(data, 0x120 + i * PlayerRoom2.SIZE); // RoomList
+                ((PlayerRoom2)GetRoom(i)).Downgrade().Data.CopyTo(data, 0x120 + i * PlayerRoom1.SIZE); // RoomList
             Data.Slice(0x289F8, 0x30).CopyTo(data, 0x263D0); // PlayerList -> Cockroach
             return new PlayerHouse1(data);
         }
diff --git a/NHSE.Core/Structures/Villager/PlayerRoom2.cs b/NHSE.Core/Structures/Villager/PlayerRoom2.cs
index 255543b..d1c6c82 100644
--- a/NHSE.Core/Structures/Villager/PlayerRoom2.cs
+++ b/NHSE.Core/Structures/Villager/PlayerRoom2.cs
@@ -54,7 +54,7 @@ public s_e13a81f4 _cfb139b9
         public PlayerRoom1 Downgrade()
         {
             var result = new byte[PlayerRoom1.SIZE];
-            Data.CopyTo(result, 0);
+            Array.Copy(Data, result, PlayerRoom1.SIZE);
             return new PlayerRoom1(result);
         }
     }
diff --git a/NHSE.WinForms/Subforms/Map/MiscDumpHelper.cs b/NHSE.WinForms/Subforms/Map/MiscDumpHelper.cs
index 7627bd7..9ea93f3 100644
--- a/NHSE.WinForms/Subforms/Map/MiscDumpHelper.cs
+++ b/NHSE.WinForms/Subforms/Map/MiscDumpHelper.cs
@@ -151,7 +151,7 @@ public static bool LoadHouse(MainSaveOffsets offsets, IReadOnlyList<Player> play
             var path = ofd.FileName;
             var expectLength = offsets.PlayerHouseSize;
             var fi = new FileInfo(path);
-            if (!VillagerHouseConverter.IsCompatible((int)fi.Length, expectLength))
+            if (!PlayerHouseConverter.IsCompatible((int)fi.Length, expectLength))
             {
                 WinFormsUtil.Error(string.Format(MessageStrings.MsgDataSizeMismatchImport, fi.Length, expectLength), path);
                 return false;
@@ -159,7 +159,7 @@ public static bool LoadHouse(MainSaveOffsets offsets, IReadOnlyList<Player> play
 
             var data = File.ReadAllBytes(ofd.FileName);
             data = PlayerHouseConverter.GetCompatible(data, expectLength);
-            if (fi.Length != expectLength)
+            if (data.Length != expectLength)
             {
                 WinFormsUtil.Error(MessageStrings.MsgCanceling, string.Format(MessageStrings.MsgDataSizeMismatchImport, fi.Length, expectLength), path);
                 return false;
@@ -188,7 +188,7 @@ public static void DumpRoom(IPlayerRoom room, int index)
             File.WriteAllBytes(sfd.FileName, data);
         }
 
-        public static bool LoadRoom(MainSaveOffsets offsets, IPlayerRoom room, int index)
+        public static bool LoadRoom(MainSaveOffsets offsets, ref IPlayerRoom room, int index)
         {
             using var ofd = new OpenFileDialog
             {
@@ -211,7 +211,7 @@ public static bool LoadRoom(MainSaveOffsets offsets, IPlayerRoom room, int index
 
             var data = File.ReadAllBytes(ofd.FileName);
             data = PlayerRoomConverter.GetCompatible(data, offsets.PlayerRoomSize);
-            if (fi.Length != expectLength)
+            if (data.Length != expectLength)
             {
                 WinFormsUtil.Error(MessageStrings.MsgCanceling, string.Format(MessageStrings.MsgDataSizeMismatchImport, fi.Length, expectLength), path);
                 return false;
diff --git a/NHSE.WinForms/Subforms/Map/PlayerHouseEditor.cs b/NHSE.WinForms/Subforms/Map/PlayerHouseEditor.cs
index 0606174..8025989 100644
--- a/NHSE.WinForms/Subforms/Map/PlayerHouseEditor.cs
+++ b/NHSE.WinForms/Subforms/Map/PlayerHouseEditor.cs
@@ -302,7 +302,7 @@ private void DeleteTile(Item tile, int x, int y)
         private void B_LoadRoom_Click(object sender, EventArgs e)
         {
             var room = Manager.Room;
-            MiscDumpHelper.LoadRoom(SAV.Offsets, room, RoomIndex);
+            MiscDumpHelper.LoadRoom(SAV.Offsets, ref room, RoomIndex);
 
             var house = Houses[Index];
             house.SetRoom(RoomIndex, room);