Hi,
rdl knows a bit about the history I am having with this issue, just wanted to report that it's not better in 0.39.2, it rather seems worse
Issue: after some random time running abz when you try to minimize the window (or if it is minimized: try to maximize the window) you get an error message and the window will not change it's state.
Previously what did work was clicking on the task bar icon when the error message popup appeared and then it would indeed change the state (while the error popup is open) but in 0.39.2 not even that will work.
The only option is to close the program (or keep it open on the screen forever) - when closing another error message appears and the sideeffect is that abz will not remember the last status when closing - when restarting it seems it will load the status it had last saved periodically (but not the state when closing).
So the latest RSS NZBs will be gone (if one had just appeared before closing with error) and latest downloaded files in queue are not marked as downloaded (will be redownloaded upon connecting) and all other stuff that it didn't remember when closing is incorrectly there/missing.
This is in Win7 x64.
Sidenote: in a WinXP VMware machine this still hardly happens, however I now have an issue there that often when downloading the par2 files suddelny are not appearing on the par2 tab anymore, it will not check and repair because of that. And when I close the program after this behaviour is seen then I also get an error message when closing in this XP machine - with the same side effects of status not being remembered like in Win7