Default v1240 Backlight display on usb

I have just got myself a v1240 and was wondering how I can set the screen display within power management to remain on when connected via usb to pc. I have played around with 'backlight time-out on AC but this doesn't appear to work with usb.

Any ideas?

Also as I'm new to smartphone having used an XDA for years...any advice on apps which I should get and/or tweaks would be gratefully recieved.
Rich
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