The default LOR Data directory is where your audio, sequence and show files are located. (Along with your Visualization folders, etc.) When you first ran Light-O-Rama you were asked where you want to put this directory. If you've forgotten where that is, just want to change it, here is how.
(Text copied from Bob at Light-O-Rama)
Close all of your running LOR programs. Not just things like the Sequence Editor, but also the LOR Control Panel (which is the light bulb icon in your computer's system tray). You can close the LOR Control Panel by right-clicking on it and selecting "Unload Light-O-Rama" from its popup menu.
Using Windows Explorer, open up the directory that contains your LOR program files. This is typically, but not always, C:\Program Files\Light-O-Rama.
In that directory, there should be a file called LORPost.exe (it might show up as just "LORPost", depending upon how you have Windows set up). Run that file.
It will step you through a few dialogs. In one of them, it will ask you where you want LOR to store data files. Tell it the directory ABOVE the directory your sequences are in. For example, if your sequences are in C:\Your Name\Shane\My Documents\Light-O-Rama\Sequences, tell it to store LOR data in C:\Your Name\Shane\My Documents\Light-O-Rama.