This Light-O-Rama Visualizer dialog appears after finishing one of the drawing wizards. On it, you can elect to create new fixtures for the entire prop, or to assign the fixtures required to fixtures that already exist.
This dialog changes depending on the type of wizard being run. However, the choices are essentialy the same:
•Create as many new fixtures as required (New)
•Create as many new full CCR fixtures as required (CCDs only)
•For each fixture required, ask if the drawing should be aded to an existing fixture or to create a new one (Existing)
Generally speaking, you should try to create new fixtures whenever possible. An exception to this may be for CCR pixels, since they are grouped by fifty at once.
The difference between "New Fixtures" and "New Full CCR Fixtures":
When creating CCD devices, the Visualizer can create the fixture in two different ways. Full CCD fixtures create the minimum number of fixtures required, where each fixtures will be a full (50 pixel) CCD, while the generic "New Fixtures" will create one fixture for each region, and then set the starting pixel for each.
In general, the generic "New Fixtures" is easier to use for editing within the simulation, but does require extra care to ensure they are set up correctly. Full CCD fixtures more correctly represent a physical CCD device, but editing them is much harder.
The Visualizer's Assign Fixtures From Wizard