Problems with RAMPS

Hi I'm new on the RAMPS and i have some problems,

I have a RAMPS 1.3 (kit) I soldered everything correctly and double checked it.
I installed Marlin 1.0.0 RC2.


1st : The led wont light even if its powered (checked the polarity i soldered it correctly)
2nd: Pronterface wont connect when i have Ramps attached

i followed every instruction i found and nothing seem to make it work (stepper motor wont move using pronterface)

Have you run the test code on the board to flash the leds and move the motors?

No really, actually Marlin is the only thing i managed to upload since anything else end up with really long compile errors.. (even using the arduino 0022).
Also can you point me to some example codes?