Options|Overlap

Overlap tracks by - Globally this effects every track. Insert a whole figure (between 0 and 10) after 'overlap tracks by'.

Overlaps in mini playlists. Set using Advanced Options, these apply to every mini playlist.

Individual overlaps do apply to tracks within a mini playlist.

Auto fader
Fade on overlap - if, for example, you have a global overlap of 7 seconds set, if autofade is enabled as the next track starts to play 7 seconds from the end of the previous one, the previous track will fade away.
Fade on stop - when enabled, will cause the current playing track to fade for the duration set here, rather than stopping instantly.
Note: Auto fader does not function in mini playlists.

Individual Track overlaps - these are set by re-naming the track's filename, within Windows Explorer or a Raduga playlist (select the track, right-click the mouse, Rename):
At the end of the track name, insert ~X (where X is the number of seconds before the track end to start the next track). The '~' symbol can usually be found with the '#' key.
X does not have to be a whole number, but should be less than 20.
Add the '~' immediately after the track name, leave no spaces.

Over-riding global setting. Individual track overlaps will always over-ride any global overlap set. You can play a track to its very end by naming it File name~0, (zero).
Individual track overlap also functions in mini playlist.

Limitations. Because of the nature of these media types, you cannot overlap CD tracks, live events or MIDI tracks that are scheduled in a direct sequence. While you can prevent MIDI files and live events from overlapping using file names such as 120~0.live, the only way to play two subsequent CD tracks is to set the global overlap time to 0. That's because you can't rename the physical name of the CD tracks.