The color
tab contains the color controls. The only color-editing ability contained
in the color tab is the Brightness control slider. Mostly these color
controls allow you to tell the RIP how to process the job. It is not meant
for color editing.
RGB Source Profile allows for specifying the ICC to use as the input profile when ripping the job. The chosen setting should match the color space of the artwork. In other words, if the image was created in the sRGB colorspace, then sRGB should be chosen, etc.
Same as above but for CMYK files.
The output profile indicates which profile to use to render the image on the printer. Since the RIP comes pre-loaded with all necessary profiles and is capable of autoselecting them according to the print settings, Auto-Select should be chosen for the majority of jobs.
Color appearance relates to the rendering intent used when rendering the file. When Photo/Normal selected, the Perceptual rendering intent is used. This results in color that is meant to match the original as closely as possible. Vivid/Darker uses the Absolute Saturation rendering intent which tends to result in more saturated artwork but less accurate colors. For most artwork and photographs, Photo/Normal should be selected.
This allows some control over the brightness of the artwork. Again, this is not meant for gross color adjustments or color management but rather, for minor tweaks. The artwork can be made a bit darker or a bit lighter.