You can download stock room from here:
After you run RUU go to your windows temp folder find room.zip and place it somewhere else because when you turn of ruu.exe it will disapere (ruu.exe clean temp folder when it's done). I think you can9t install ruu if you don't have usb charge only and usb debuging.
But you can:
Change room.zip name to pd98img.zip
put it on sdcard (before that you have to format sdcard to fat32)
put sd card in phone and go in hboot (power boton + volume down)
wait a few second and hboot will start checking pd98img.zip automaticaly
when it's done, would have to press volume up to start installing rom.
Be sure that your phone is full charged (at least 50%), and that you don't shut done your phone until it's done because it will be bricked.
I think that it's a software problem because i don't see relationship between touch and backlight in hardware.
And flashing software is the easiest way to try fix something.
If that don't do work you can try with hardware fix.
Something like that:
P.s.: Sorry for my bad english.
---------- Post added at 03:00 PM ---------- Previous post was at 02:49 PM ----------
Oh, I remind one thing. In picture I have posted you, you have connector if I remember very well it's for that bouth, so you can detach it, clean it with alcohol and connect it properly.
This may do the work.