Hi Robin,
At this time, if you move the mouse, the arrow key option will become disabled until you do press the TAB key. I'll be rethinking how this works knowing that alot more people are starting to use remotes.
Perhaps a timer that every so often sets focus back on one of the buttons would help.
I'm confused though if you are using a remote, why would you be using a mouse?
One other option that I've seen users do is assign numbers to the buttons if they only have 5 or 6 options. For example:
1. Play Movie
2. Watch TV
3. Internet
So then they can just hit a number on the remote instead.
Also, you could just simulate TAB and SHIFT-TAB to navigate.
One other thing I want to do is to allow the user to disable a button as being clickable or part of the button sequence.