I'm using WhileIdle on two machines.

You should consider changing three changes:

• WhileIdle is visible if you switch between programs with ALT+TAB, it should be hidden
• There should be an option to hide WhileIdle from the task list (this is possible, I've done this years ago)
• Alternatively make WhileIdle installable as a service, I used "Servify This" but it didn't work for some reasons