Logitech Tab Key problem

[Deastman]

I have a new Logitech M705 wireless mouse and the latest setpoint software. I cannot program the tab key to function as a tab keystroke. When I press the mapped button it switches applications. A search on the Logitech support forums shows the same problem with no apparent solution. Anyone have a Logitech mouse with a mapped tab key? I there a way to map Chief to advance to the next item with another key (or combination)? Same on both my Windows 7 and 8.1 computers.