I'm also enjoying the new version, but i do have some issues with the new game startup and shutdown functionality.
The new "Automatically close the startup screen when the game window appears (and show the shutdown screen when it closes)" option seems to hook into an extensive script i made which starts an emulator, which starts a game. So the game startup screen turns to black after two seconds, while the game takes a lot longer to load. Disabling this option seems to work, but the "Game Shutdown Screen" doesn't seem to work as i'm using the Escape button to quit my emulated games and this simply shows the Launchbox app again, the Game Shutdown screen is nowhere to be seen. Strangely enough when I ALT+TAB to that window, the Game Shutdown screen triggers, just as in the previous version.
My current fix is to disable the "Automatically..." option and simply forego the use of the shutdown screens for now.