I would like to use right-Alt (AltGr) as ⌥ key. These are modifier keys right of the spacebar on MS 4000 Keyboard: . I currently have the Application key mapped as ⌥, but AltGr would be less clumsy.

Also, there is only Alt sticker on my MS 4000, and currently my Alt [Gr] doesn't function as any modifier key.

I've already looked in KeyRemap4MacBook and the question AltGr keyboard shortcuts on MacOS?.