[Pharo-users] Unresponsive/frozen Gui

I experience that issue once in a while when I leave the pharo 6.1 on windows and when I come back to it the UI is frozen. Now I download pharo with moose image and it started to happen again (BTW I couldn't install Moose in my pharo 6.1 using Metacello command) I wonder if it's something that happens to many users and I have to get used to it (ui freezes) or there ways to avoid it. Again, maybe it's a windows specific problem and most of the pharo users are either on Mac or Linux.