
Placing this into the blog, since normal googling gave no solution on this one.
Problem: VMWare Fusion autodetects Logitech diNovo Mac edition (at least with European keyboard layout) as Macbook keyboard. Which makes it use the numeric pad Enter as AltGr.
This is how to make it use the right Cmd key as AltGr.
1. VMWare > Fusion > Preferences > Keyboard & Mouse
2. Remove the current 'cmd' shortcut (pointed to Windows key on mine) or reuse it
3. Don't try pressing the key, just leave the cmd emblem enabled and the key field empty
4. Map to Right Alt (AltGr)
That's it.
Actually, this should have been obvious, and I dare not think how much googling I tried in vain. What mislead me was the mapping of CMD without saying whether left or right should be mapped. Seems the "enable OS X CMD" setting overrides the left key (only) so I get what I want: left for OS X, right as Alt-Gr. Maybe VMWare should do the UI better, but I don't exactly know, how. For people with Apple keyboards I guess the thing "just works".