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I'm no CCD expert either but these look like hot pixels. They appear on your light and dark frames and most are rendered more or less invisible by calibration. The really bad (= bright = close to full well capacity) hot pixels though leave a relatively darker pixel after calibration that is made worse by stretching and become obvious in the higher signal areas of your image. The only way to remove these after the fact is to clone them out. The best thing to do is dither your light frames so they don't appear in exactly the same location in your lights. Then you can use a sigma reject algorithm and/or do a median combine to eliminate them altogether. Dithering is extra work but it is very effective at removing artefacts.
CCDsoft 2 also allows you to create bad pixel maps for your sensor and, I think, it can be applied to average the bad pixel using the surrounding pixels thereby eliminating them.
Cheers, Marcus
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