An AutoHotkey script that changes these key combos:
AltGr + a -> ä
AltGr + e -> ë
AltGr + i -> ï
AltGr + o -> ö
AltGr + u -> ü
AltGr + s -> ß
AltGr + Shift + a -> Ä
AltGr + Shift + e -> Ë
AltGr + Shift + i -> Ï
AltGr + Shift + o -> Ö
AltGr + Shift + u -> Ü
AltGr + Shift + s -> ß (I know shafer's s has no capital, but in the event you accidentally try...)
AltGr + CapsLock + a -> Ä
AltGr + CapsLock + e -> Ë
AltGr + CapsLock + i -> Ï
AltGr + CapsLock + o -> Ö
AltGr + CapsLock + u -> Ü
AltGr + CapsLock + s -> ß (I know shafer's s has no capital, but in the event you accidentally try...)
Latest AutoHotkey release is reccommended for this script, it can be found here:
https://www.autohotkey.com/