Customize marlin 1.2.0

Hello!
I decided to put on your REPRAP 1.4 new firmware. In the previous (1.1.0) does not work Auto bed level.
I can not figure out how to configure it. All files scattered in folders and there is no manual. I tried to collect myself.
I used the old configuration file.
But the compilation is stopped in the file Firmware Customization.h error Compilation using cores other than those provided in this distribution are unsupported.
Tell me how to set it up?

There is no Marlin 1.2.0 in the "official" branch of github.... The newest version is 1.1.RC2 which is a release candidate, not guaranteed to work stable.

Can you provide the link to Marlin 1.2.0 ?
-Olaf

There she is
Merlin Dev
I was quite happy with version 1.1.0. But when using the auto level Z axis starts moving in the opposite direction.

Edited 1 time(s). Last edit at 10/17/2015 05:59AM by pirat777knj.

Lookup Toms Guides on youtube, he has a great section about configuring ABL. It works fine for RC2, and with four points auto bed leveling does run backwards from the previous stable version yet still worked fine, when I bumped it up to 9 points it ran in the positive directions like I was used to.

Thank you. Good opens. Problem was solved.
I do not know what to uncomment one line.