Then under each of them you add two string values (REG_SZ) where one should be named "File" and the other "Parameters". "File" should point to the programfile you want to run and "Parameters" if the programfile should start with some parameters. If you don't want/need any parameters you still have to create the string value Parameters, but just leave it empty. Below is en example to make Fn-F9 start notepad without any parameters:
If you have some spaces in the path to the programfile you might have to add " in front and at the end when you add a value to the string value "File. On my computer i only managed to get this working for Fn-F2 - F9 and F12. I did not manage to get Fn-F1, F10 and F11 to do anything. I didn't try very hard so maybe there are some kind of trick to get those working as well.
To customize the blue Thinkpad button you have to create a string value named "File" and do the same thing under here:
For this one it seems like the Parameters string value isn't needed.
Since you need some of the Lenovo software to make these keys work in the first place (like hotkey and comm utilities) i gues these utilities have to be installed for the Fn-xx keys to do anything even if you decide to customize each one of them.
Warning : Make sure to make a backup of the registry if you are to make changes/edits to the settings....