VistaSwitcher inactive while PC busy.

I used TaskSwitchXP for years and it works well. Recently changed to W7 and VistaSwitcher. In normal circumstances it works alright but not when things are busy. If the PC is busy VistaSwitcher does nothing. When the PC becomes less busy VistaSwitcher flashes rapidly as it catches up with all my attempts to switch window. If I press enter on a file, and the app is busy for a while opening...