I needed to assign the keys without an active profile first (because I usually use profiles). Makes sense, I guess.
my ini: (order is Ö, Ü, Ä)
[Keys]
2=N192,8,1061,0 -{'@key: Press=engine 1 autostart }-
4=N186,8,1062,0 -{;:key: Press=engine 2 autostart }-
6=N222,8,1063,0 -{#~key: Press=engine 3 autostart }-
Here is the log. Seems all keys were registered.
375 LogOptions=40000000 00000001
17500 *** Entered Keys option page ***
66985 *** Exiting Keys option page ***
136797 KEYDOWN: VK=192, Waiting=0, Repeat=N, lParam=2555905 (0x270001), Shifts=0
136797 FSUIPC Control Action: Ctrl=1061, Param=0
136797 .. This key is programmed in FSUIPC7 'Keys' options
136891 KEYUP: VK=192, Waiting=0, Shifts=0, lparam=3223781377 (0xC0270001)
136891 .. KeyUp received from FS but not programmed
137969 KEYDOWN: VK=186, Waiting=0, Repeat=N, lParam=1703937 (0x1A0001), Shifts=0
137969 FSUIPC Control Action: Ctrl=1062, Param=0
137969 .. This key is programmed in FSUIPC7 'Keys' options
138063 KEYUP: VK=186, Waiting=0, Shifts=0, lparam=3222929409 (0xC01A0001)
138063 .. KeyUp received from FS but not programmed
139110 KEYDOWN: VK=222, Waiting=0, Repeat=N, lParam=2621441 (0x280001), Shifts=0
139110 FSUIPC Control Action: Ctrl=1063, Param=0
139110 .. This key is programmed in FSUIPC7 'Keys' options
139188 KEYUP: VK=222, Waiting=0, Shifts=0, lparam=3223846913 (0xC0280001)
139188 .. KeyUp received from FS but not programmed
154391 === Hot key unregistered
154391 === Stop called ...
154407 === Closing external processes we started ...