Unknown issue when decompiling rooms.

[HeySteets]

Upon trying to decompile the rooms, I get thrown this error: System.IndexOutOfRangeException: Index was outside the bounds of the array. at Altar.Unpack.Serialize.SerializeRoomTile(RoomTile tile, BackgroundInfo[] bgs) at Altar.Unpack.Serialize.<>c__DisplayClass30_0.<SerializeRoom>b__3(RoomTile t) at Altar.Unpack.Serialize.SerializeArray[T,TRet](IEnumerable1 coll, Func2 converter) at Altar.Unpack.Serialize.SerializeRoom(RoomInfo room, BackgroundInfo[] bgs, ObjectInfo[] objs) at Altar.Program.Export(ExportOptions eo) at Altar.Program.<>c.<Main>b__9_0(String verb, Object vo)

Not exactly code savvy, so I have no clue what it means. Any help would be great!