The main screen sometimes does not properly refresh after recalling between map sectors. Most of the times it was snowing in-game, but I don't know if the problem is connected with that. It's easy to get the main window working properly again, I just have to somehow refresh the main window (opening inventory list, world map etc.).
It does not happen very often, usually about every 15th recall.
Here Is my main screen after teleporting from Gondolin to Bree.