Looking at your raw file, I think overexposure is the key point here.
As the LEDs in the stoplight are themselves hopelessly overexposed, I see no solution to their being the wrong color save for making the exposure at a lower level and bringing up the shadows, or hand-adjusting the LEDs to be the color you want. The brilliant red color is simply out of gamut and beyond the dynamic range of the sensor. How the various raw converters handle the transition into overexposure differs greatly; Canon tends to try to preserve as much of the color as they can while Adobe tends to desaturate so as not to portray the
wrong color. Looks like C1 is somewhere between the two, though I have no personal experience with it.
Regarding the jaggies... Though the raw converters all provide their own sharpness enhancement settings, I find that for the best possible end results one should leave those sharpening settings "off" or at the minimum possible value in the converters, and use a sharpening tool on the image proper after conversion.
Consider, for example, your stoplight as converted in Photoshop with 0 sharpening, then processed by me (using HDR techniques to get the maximum dynamic range out of the file and sharpened with my own fractal sharpening actions).
I find it very interesting that Canon's own in-camera processing has rescued as much or more highlight detail as any of the methods (as evidenced in the preview JPEG embedded in the Raw file), and has done so with fairly little distortion. I've upsampled this one to twice original size for easy comparison with the others.
Another thing that may be influencing these results is the fact that the anti-aliasing / IR block filter in most Canons is blue-green colored, meaning it's blocking some of the red light as well. The additional math required to bring the red values back in line with the blue and green channels may be getting confused by the abrupt transitions into overexposure.
Lastly, it's now known that Canon cameras apply some sharpening to the raw data before storing it in the .CR2 file (Chuck confirmed this some time back). I've never been able to figure out why they do this, but sharpening the data does adversely affect sections of images that traverse from dark areas into brilliant highlights. That is indeed happening in this image, and may well be responsible for the visible nasties in the DPP image.
Summary: From what I can see, Capture 1 is handling the red color and the transition into overexposure nicely. It's pretty clear they have some special processing to handle these conditions. DPP has provided a bit sharper image overall, but with nasty side effects at the transitions into overexposure. I would be tempted to see how the other Canon converter does - the one that used to be called EVU, and which closely matches the algorithms in the camera.
-Noel