I am run world of tanks 9.8(now wot9.9) RU on ubuntu 14.04.2 + unity DE + playonlinux 4.2.8 ... choose wine version 1.7.42-1.7.47 for wot and run game in fullscreen mode.Then I choose in menu(in wot) window-mode and my mouse run in wot-window only ... when on 1.7.41 mouse in window-mode can run out wot-window ... `Mouse warp override` - problem not decided.
I write on winehq.org https://appdb.winehq.org/objectManager.php?sClass=version&iId=32270#Comment-94954
and me answered
"Hello! I can't reproduce this behaviour on my PC. I'm using Linux Mint (based on Ubuntu) with MATE (Gnome 2 fork) and I don't use PlayOnLinux. It works for me with wine 1.7.44 - mouse runs in wot-window as well as all over the desktop in window-mode. At your PC it may depend on updates for Unity or PlayOnLinux, or all together with wine. Nevertheless I think it's not a wine bug."