I was asked to make a sheet with the chord notation.
Here it is. But this is my two cents about this sheet:
It is not common to use them in Frahm's pieces. Chord notations are used in songs and jazz music, but they are not 'clear' enough for this kind of compositions.
You should read this explanation about chord progressions, -see the first answer, that somehow describes what I want to say:
Chord notations are used to notate the chord progression, but you need more info to play Frahm's pieces right. Every note has to be specifically on the place where it is, you can't put them elsewhere in the chord.