Here I am!!
First of all, nice selection of comics! I'm reading Martin Mystere too!
1) Try checking the filename of those CBRs...
Korku -5 Tay .cbr >>> Korku -5 Tay.cbr
Ken Parker 01 Uzun Tufek.cbr >>> Ken Parker 01 Uzun Tufek.cbr
It worked fine after this trick!
2) The contrast/brightness box works for me!
I found you have:
Is it because you packed files from different folders? Try renaming the last image to 3.png
Anyway, it worked fine also OOTB!!
Here you can see a screenshot with the contrast/brightness box. The image in the background is slightly tweaked to improve the look!