Just to be clear. I'm not using a "mouse program" this is a setting in Windows. It is part of the OS. It is turned on by tweaking the registry so is not part of the "mainstream" configuration. The easiest way to do it is to use the Microsoft TweakUI tool. It is sometimes called X-Mouse as it was the default behaviour in X-Windows.

Yes, it is nice that BIAB doesn't fiddle with the registry, but this has nothing to do with the way it handles window events. Something in BIAB is telling the window manager to bring its window to the front when it shouldn't. It would be nice if it didn't.

Regards

Andy