I have done some testing during the last 4 weeks.
I had 4 Galaxy S2 and every one has the yellowish tint problem on the left side of the display. Some had a more or less camera problem (red dot, sharpness) some had issues with GPS and two a very strange display (totally dark). My current S2 is not perfect and the display has also the yellowish tint problem, but it is the best out of 4.
I was so suprised when I flashed the XXKH3 coming from KE7. After reboot I had to activate the lockscreen one time and the yellowish tint was completely gone. After the next reboot the yellowish tint was there again but after lockscreen activiation/deactivation the tint was fixed (as already reported in this thread).
So, I testet some different ROMs to see, which one I like:
Litening ROM 6.1 XXKH3: NO tint fix
Galnet MIUI base MIUI 1.9.9 and 1.9.16: tint FIXED
Leomar Revolution ROM 2.6 XXKH3: tint FIXED
CM7 (last week): NO tint fix
Tint FIXED means, you have to activate the lockscreen at least one time to see the fix.
Someone reported, that CM7 would fix the tint problem also, but the tint problem stayed with the CM7 build I tested last week.
BTW, I will stay with Leomar Revolution ROM. CM7 is great, but too experimental and Galnet MIUI is very, very nice, but also too experimental (I had some problems with their own framework, problems in menus etc.) and unfortunately, as well known, both no BT audio support, which is needed for handsfree sets.
It would be great if CM7 could provide this tint fix for the S2 also.
From what I have read CM7 has it's own color engine (and there are fixed color profiles in the UI, but none of them is usable, because of wide spread for standard factory models). But it would be possible to calibrate the display perfectly if the CM7 UI would provide the needed settings (RGB values for gain/bias or multi-point calibration, gamma calibration, even sharpness/DNR etc.).
Supercurio is working very hard on a color management solution for the S2.
Maybe he is able to do this not only for stock based ROMs but also for CM7 based ROMs (called ASOP I think? correct?