Broken poer button

I managed to broke my power button during opening of back cover.
I put a card under the circuit board and damaged something responsible for turning reader on/off.

I exchanged memory card in order to switch to android. After assembling up the device I tried to turn it on and nothing happened.
I opened it up again and unfortunately I think the power button is broken for good. I found some tiny loose plastic and metal parts in area of power switch.
I put back old memory card and connect reader to pc. It turned on.

Is there anything I could do to assign power button with light button either in android or original software?

I can still use reset button to power on reader but it won't be very handful.
Can I put memory card with android in and instead of switching on reset device or connect it to computer? Will it work the same as with Nickel?
I don't want to risk loosing contact with my device. Power button seems to be quite important:/ I could live without light one. I wish I broke this one instead.
So guys if you're opening it for the first time be careful. Especially when you're opening it close to power button.

One more question:
There are some covers with auto on/off. Where is the sensor located? Is it work independent of power switch mechanism? Will it works on android?

Thank you for any :help: