I think that the color problem is not related to kernel bat display & touch overlay. I assume that they used different ones on different series of Y300 or just same manufacturer switched to different controller! To explain this for instance Clarkiieh has the UK version of phone bat the FusionX rom solved his color problem & FusionX is actually based on firmware meant for Asian market. It should be best to address this like that to Huawei!
I don't even know where color settings are located other then kernel. That whot i know is that display manufacturers mostly use third party controllers & that is not uncommon that after development of new revision of one (optimized layout, minor pin change) old one is withdrawn from production! I am guessing that this is a source of problem. Perhaps answer lies in touch firmware?
Glad I could help, that's if i did I still dont get why the very first time you lock the screen on the phone it doesn't do what any normal phone does and the screen goes fully black. The only and very best way I can describe it is this...
The screen turns of but it Starts from the top and works its self down to the bottom.. in a sort if sliding motion its weired and only does it on the first lock you preform on the phone
But before this happens the display and colours in the phone and nice and bright And shiny but afterwards there dull and look drained, tillaz's rom fixed this for me I am sure, the oranges look better and every other colour for that instance