Jorge,
I find, particularly for a modified DSLR, Deep Sky Stacker does a terrible job of the colour balance.
Play with the settings in DSS in RGB levels to get the balance right before you save.
Same with the Luminance and Saturation levels.
I crank up the saturation levels up to 17% to 21% and then adjust accordingly RGB and Luminance before I save.
It's best to get the image as good as you can out of DSS before processing in other software.
Your data looks good - it's about getting the colour balance and saturation levels correct.
Also, you can save a lower Luminosity image to use as your core - so save 2 versions in DSS.
Here is an example with my modified 400D and 12.5" f/5 at ISO1600 200 second exposures and 5 seconds and 30 seconds for the core:
https://www.flickr.com/photos/johnka...ream/lightbox/