MTK6753 Rom Flashing Problem (Battery not Charging)

Greetings~
I was able to flash the full rom of MTK6753M (marshmallow, 3.18 kernel) to a MTK6753 (lollipop, 3.10 kernel) phone that i have. I didn't really port anything since the difference in kernel versions, but just flashing the rom seems to have worked. My phone seems to have been updated from Lollipop to Marshmallow.

Most parts of the hardware works (SIM, Wifi, Bluetooth, Audio) except for the following:
1. capacitive keys are reversed (back button and the menu button)
2. screen rotation is reversed
3. battery is not charging

I tried searching online about the battery problem and what i found so far is that the lk.bin file or "little kernel" in the rom may contain drivers for the LCD screen and battery charger.
Is it possible to decompile the bin file or to port the battery driver? (or maybe I'm looking in the wrong direction with this problem)

Is there a way to fix the battery problem?

Thanks in advance~



P.S.
Here are some information about my phone:
MTK6753 Octa-Core (64-bit)
5.5inch Screen
Android 5.1 (3.10.65+ kernel)
2gb RAM/16gb Storage
4G/LTE ready
2,200 maH battery

Here are some info about the firmware I flashed:
MTK6753M Octa-Core (64-bit)
6inch Screen
Android 6.0 (3.18.xx kernel)
2gb RAM/16gb Storage
4G/LTE ready
2,500 maH battery

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