Dude messing with the ramdisk or even the kernel probably ain't getting data working working!
To get data working you are going to have to dig inside the Tom framework. Without the source that's gonna be a bunch of smali editing which is like reading raw bytecode.
The ramdisk may have something to do with data initial the init.RC but its probably not honna fix it. For that you are gonna have to pull apart the framework Java files. Its not fun at all.
As for editing the kernel, without the source for the kernel you want to edit there us nothing besides ramdisk Modding you can do because the boot.img is a c compiled binary kernel image. If you want to add governors and tweak the kernel more than what's possible in the ramdisk, or add anything to the kernel, you need the source code for the kernel, and a Linux/Unix enviroment to compile all the c code of the kernel source into a working android kernel. Where are you guys porting this miui port from? Because you will nerd there kernel source to compile the kernel.
That still wont help data though! You need the framework source code( wrote in Java) in order to easily moddify and compile the framework of yge rom. Seeing as how miui us still closed source on the rom framework its not gonna be easy.
First place yo start us by recompiling framework.jar and looking around in there.
