A detailed button guide is up at RioCar.org which describes the exact functions of all buttons including how they behave in tuner mode.

If you want to increment the frequency without "scanning", I believe you have to use the remote. All the other buttons on the front panel are already spoken for in tuner mode.

Note that the button guide is written for the 2.0 software, it's possible that the 1.03 software has slightly different behavior.
_________________________
Tony Fabris