I've made this configuration with a couple of resistors to get exactly 120 ohms.

Now I get this error message after the Rx led on the Uno flashes three times:

This is the orientation of the ATTiny in the bread board wrt it's connections.

(I previously bent the legs of the cap for a better fit in the bread board but no results there)
(I'm going to clear everything today to put an extra lamp on the ceiling tomorrow)
EDIT:
It's working now!!!
I made the rookie mistake of not connecting the ground of the chip after I used the ground lead for the resistors and I left the cap and resistors out and now it works.
So the auto reset is not disabled. I also connected a led to pin 9 to see the heartbeat.
Thanks guys for the support.
Here a short vid of the result.
Brake lights for my Team Associated SC10 short course race truck.
(you cannot see it clear on the vid but the leds burn when the brake is engaged, with the potmeter I can tune the moment of engagement to follow trim of the ESC if necessary)
http://www.youtube.com/watch?v=WITOf1tZjXc