Hi JulienD,
Do you have the Ultimate robot Blue with Oiron board?
If you want to control the robot ARM with IR controller, you need program yourself to achieve it.
Upgrade firmware for Orion board will clear the previous program uploaded to the main board and the IR controller won’t able to control the robot ARM.
For your first post, when you want to program the Orion board with Arduino software, you need choose the Arduino/Genuino UNO instead of Arduino Leonardo.
Anyway, you may try to program on mBlock to make the IR controller control the robot ARM.
The best way to control the Robot ARM is to use mobile APP (Makeblock APP through Bluetooth connection). In this case, you can just rest default program for the Ultimate and don’t need to program by yourself)
Since you want to control by IR controller, you can program for the Robot ARM with the mBlock software:
Program the arm, actually, you only need to program the 37 motor which control the arm and the motor in the Griper.
About programming with mBlock IDE for the 37 Motor and Griper, you can see the 37 motor is connected to Port 2 on Orion board and Gripper is connected to Port 1 on Orion board. Below is a example program.
Finally,you need program the IR controller either refer to this post: http://forum.makeblock.cc/t/trouble-programming-ir-buttons-in-3-2/3131/9