Does anyone know how to remap `Caps Lock` to `AltGr`/`Alt`+`Ctrl` on Windows 7?

Closest I've come to solving it is using SharkKeys, but if I try to map anything with `AltGr` it says SharpKeys doesn't know about the key.

Here's the old bug report about it: <https://sharpkeys.codeplex.com/workitem/10375>

I've been searching a lot, but all the registry hacks are how to map it to `Shift` or `Ctrl`, nothing about `AltGr`.