Within the Cues window, the green bar shows you the currently active cue, while the yellow bar highlights the next cue (which will become active if you press Go). You can change which cue is next by simply selecting it, using either the touch screen or the arrow keys. The cue will go yellow, and become active when Go is pressed, or the playback fader is raised. Once the end of the playback is reached, the first cue will be selected as the next cue, resulting in a loop.
Individual cues cannot be renumbered. If you need to reorder a few cues, you can do this by moving them to the cue number you need.
The whole playback can be numbered, by opening the playback's settings, and tapping Advanced -> Renumber.
When running through your cues, the highlighted cell in the cue list window (blue cell) will be the cue number of the Next cue, highlighted in yellow. Pressing Enter will allow you to type into the cell. This will not renumber the cue, but instead allows you type in the cue you wish to be next, and press Enter. The Next cue jumps you to the cue you typed, (if present), meaning the next go button press will run that cue.