In the main, there are two kinds of color models at issue, one radiant, one reflective. Corel's products, right or wrong, take the view that the work done on them is ultimately for output to a printing press, color photographic lab or a slide burner.
The radiant model RGB, is the one used for work intended for monitor viewing, AV work and for slide burner output. The reflective model, CMYK is the one intended for print.
If you are working in CMYK and you have not switched off your color management module the program will attempt to alter the monitor colors to replicate the output of the printer you have specified.
Switch it off.
Always work with an ink manufacturers guidebook, or Printers Pal,or similar color tables when colorising work for process color press. Ignore the bloody monitor! Set it so your work looks like it should, to your eye, then just before you send it out to the prepress guys, set the colors on the job by using the CMYK pallet so the ink specs are correct BY THE NUMBERS. They will print properly that way, even if they look stranger'n hell on the boob tube.
If you are designing for video, or for computer monitor, then use an RGB model; if you employ a CMYK pallet the colors will tend to be muddy, or carrying too much "gamma". (Third level of shadow, and achieved on a printing press by printing a black image under the three colors that should make black, but cannot due to the transparency of inks. Why they just don't say "black" or "undercolor", I do NOT know).
Obviously with RGB you do not need an undercolor, as 100 per cent saturation means white (the three colors combine to make white light as in nature, so as you reduce the saturation they lose brilliance and contrast and go to darkness, so at 0 color they ARE black.
Whereas with an absorbant, or reflective color model, as the colors become stronger they tend to black. Which makes them a bit hard to synthesise on a radiant color device (a monitor).
What you have to give thought to in RGB is that no two monitors are the same, and so a dreadful thing called the 'web safe pallet' has been born...five shades of green and all of them would make a lime puke, is the best description I have heard.
Once again, better to switch off the Color Management software, and trust your eye, then run your job on as many monitors as you can, and try for happy mediums.
With print work go to the guys in the splattered overalls in the big room with all the machinery and paper zooming across rollers. Talk to them, get the real deal... most people who work in so-called "prepress" think color comes out of a macintosh.