You can't upload Configuration.h. What you do is edit it, compile whatever your firmware is (Marlin?), and upload the result (the compiled firmware) to the Arduino. It's not nitpicking, I've seen people try to feed Configuration.h into avrdude.
The RAMPS test file, if it is what I think it is, overwrites the firmware, so you have to upload the compiled firmware again for the Arduino to talk to Pronterface.
Before you worry about limit switches and thermistors, try to fix the fact that the test firmware does not move the motors. It seems that power does not reach the drivers, or they remain disabled. You can use a multimeter to check that the supply voltage is present on the supply terminals, and that it also reaches the respective pins of the drivers. Be careful not to short anything while power is applied. Also check that the drivers are plugged in the right way round (although it may be too late for them if they weren't).
Once you get the motors to run, what seems to happen with the other stuff is a short-circuit (too little data to be sure, but that would be my first guess). Finding that is just a matter of getting the board to work with nothing connected, then connect stuff until it stops working, and so figure out what causes it to stop working. Once you've done that, it should be easy to find out why, and fix it. (Reminder: do not connect or disconnect anything with the board powered. Remove both motor and USB power first.)
I'm sorry there doesn't seem to be an easy way -- this
is the easy way. Imagine what you'd do if all the parts were soldered permanently, and the board simply did not power up.