Hi,
Sorry to hear the system is not working better.
If the keyboard itself was actually bad though, I would think whatever didn't work, would not work regardless of the temperature, so it makes me wonder if replacing the keyboard would actually fix the problem and there isn't something else wrong although it's probably the first thing to try if you had to.
Anyway, just wondering if you had a USB keyboard around you could plug in when the problem happens just to check if anything happens to it when the notebook keyboard is not working, but may not be very conclusive if the USB keyboard is still okay.
Not sure how well this will work, but you might contact eStore to see if they can order or plan to carry the S46CM keyboard, but they may not always be able to or it may take a long time.
Anyway, hopefully others have better ideas and good luck in getting that solved.